prereq-build: fix `which` detection on Fedora

Fix Fedora 34/35 issue where 'which' detection of 'which' wasn't working
because Fedora use alias and proc

Signed-off-by: Jani Partanen <rtfm@iki.fi>
[fix commit subject and message]
Signed-off-by: Paul Spooren <mail@aparcar.org>

diff --git a/include/prereq-build.mk b/include/prereq-build.mk
index 9242407b1896321b376701a8f8928157c95cfcd0..750d3347162ce7d3d8f97c59530dc0a525346f8d 100644 (file)
--- a/include/prereq-build.mk
+++ b/include/prereq-build.mk
@@ -186,7 +186,7 @@ $(eval $(call SetupHostCommand,rsync,Please install 'rsync', \
        rsync --version </dev/null))
 
 $(eval $(call SetupHostCommand,which,Please install 'which', \
-       which which | grep which))
+       env which which | grep which))
 
 $(STAGING_DIR_HOST)/bin/mkhash: $(SCRIPT_DIR)/mkhash.c
        mkdir -p $(dir $@)