perf: fix build on PowerPC

perf: fix build on PowerPC

Building perf's intel-pt-decoder fails on both PPC32 and PPC64:

/home/stijn/Development/OpenWrt/openwrt/staging_dir/toolchain-powerpc64_e5500_gcc-13.2.0_musl/lib/gcc/powerpc64-openwrt-linux-musl/13.2.0/../../../../powerpc64-openwrt-linux-musl/bin/ld.bfd:
/home/stijn/Development/OpenWrt/openwrt/build_dir/target-powerpc64_e5500_musl/linux-qoriq_generic/linux-6.1.86/tools/
perf-target-powerpc64_e5500_musl/perf-in.o: in function `insn_set_byte':
/home/stijn/Development/OpenWrt/openwrt/build_dir/target-powerpc64_e5500_musl/linux-qoriq_generic/linux-6.1.86/tools/perf/util/intel-pt-decoder/../../../arch/x86/include/asm/insn.h:64:
undefined reference to `__le32_to_cpu'

Add NO_AUXTRACE=1 to MAKE_FLAGS for LINUX_KARCH powerpc, which disables
build of intel-pt-decoder on both PPC32 and PPC64.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>