treewide: replace which with command -v

Fix shellcheck SC2230
> which is non-standard. Use builtin 'command -v' instead.

Once applied to everything concerning OpenWrt we can disable the busybox
feature `which` and save 3.8kB.

Signed-off-by: Paul Spooren <mail@aparcar.org>

build/i18n-init.sh

@@ -4,7 +4,7 @@ PATTERN=$1
 SCM=
 
 [ -d .svn ] && SCM="svn"
-git=$( which git 2>/dev/null )
+git=$( command -v git 2>/dev/null )
 [ "$git" ] && "$git" status >/dev/null && SCM="git"
 
 [ -z "$SCM" ] && {