ucode: update to latest Git HEAD

ucode: update to latest Git HEAD

bcdd2cb examples: add module search path initialization and freeing
ee1946f ubus: fix GCC strncpy() truncation warning
131d99c lib: introduce three new functions call(), loadstring() and loadfile()
8e8dae0 lib: introduce helper function for indenting error messages
476f02b lib: simplify include_path()
d84b53a source: avoid null pointer access in uc_source_runpath_set()
c43a54f types: gracefully handle unpatched upvalues in ucv_free()
e2fb11a README.md: document gc() function
b41cb2d main: introduce -g flag to allow enabling periodic gc from cli
85d7885 lib: implement gc()
47528f0 vm: support automatic periodic GC runs
381cc75 types: treat vm->exports as GC roots
fcc49e6 compiler: add import statement support for dynamic extensions
c9442f1 vm: introduce new I_DYNLOAD opcode
b6fd8a2 lib: internally expose new uc_require_library() helper
a486adc vm: don't treat offset 0 special for exceptions
41ccd19 compiler: don't treat offset 0 special at syntax errors
b4a3f68 compiler: improve formatting of nested syntax error messages
5d5dadc program: remove now unused uc_program_export_lookup()
304995b compiler: rework export index allocation
506cc37 compiler: fix deriving module path from source runpath
54b7fac compiler: enforce stricter module compilation rules
d62e372 vm: don't initialize upvalues for module functions
b856602 program: add serialization and deserialization for module function flag
d7d1bde compiler: add a flag denoting module functions
156d584 treewide: unexport libucode internal functions
10e056d compiler: add support for import/export statements
862e49d compiler: resolve predeclared upvalues
78dfb08 compiler: require a name in function declarations
afd78c1 compiler: fix reported source position in inc/dec operator error
e1c3db0 tests: run_tests.sh: substitute dynamic test directory path in output
3c168b5 vm, cli: move search path into global configuration structure
d85bc71 vm: introduce import and export opcodes
365782e vm: honor constant flag of objects and arrays
6becc64 vm: transparently resolve upvalue references
3418967 vm: gracefully handle unresolved upvalues
50cf572 program: add function to globally lookup exported name
c441f65 program: add infrastructure to handle multiple sources per program
2322468 program: fix reporting source position of first instruction
9c9a9ec program: fix en/decoding debuginfo upvalue slots in precompiled bytecode
41114a0 source: add tracking of exported symbols
70ae304 lib: honor constant flag of arrays
3c104f5 types: resolve upvalue references on stringification
3a6f9cb types: add ability to mark array and object values as constant
b738f3a lexer: recognize module related keywords
03c8e4b lexer: rewrite token scanner
fd433aa lexer: fix parsing with disabled block left stripping
557577a rtnl: fix parsing/creation of IFLA_AF_SPEC RTA for the AF_BRIDGE family
35c6b73 compiler: fix stack mismatch on continue statements nested in switches
f673096 uloop: end uloop on exceptions in managed code
2e5426c ubus: end uloop on exceptions in managed code
c024270 rtnl: expose IFLA_STATS64 contents
d3c58c0 rtnl: expose ifinfomsg.ifi_change member
c4dde50 rtnl: update NETLINK_GET_STRICT_CHK socket flag with every request
7ef0d02 nl80211: fix NL80211_SURVEY_INFO_NOISE datatype
9a2e592 compiler: fix stack mismatch on nonmatching switch statements with locals
03c8ca5 nl80211: recognize further NL80211_STA_INFO_* NLAs
a1ed566 struct: add optional offset argument to `unpack()`
230e595 rtnl: fix segmentation fault on parsing linkinfo RTA without data
523566d rtnl: zero request message headers
56be30d rtnl: fix premature netlink reply receive abort
1347440 rtnl: avoid stray "netlink: %d bytes leftover after parsing attributes."
44b0a3b struct: fix packing `*` format after other repeated formats

Also package uloop binding module which has been introduced by a previous
ucode update and introduce a host build with the basic set of modules.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>