common: simplify logic to find git

From chroot-git 2.33.1, we always have an executable named git
for other build infrastructure and lints.

Let's remove the shenanegan to find which git to be used, prepend the
path to chroot-git's git into $PATH, and let's the shell call the
correct git for us instead.

common/scripts/lint-version-change

@@ -13,20 +13,18 @@ if ! [ "$base_rev" ]; then
 	die "usage: $0 TEMPLATE BASE-REVISION [TIP-REVISION]"
 fi
 
-if command -v chroot-git >/dev/null 2>&1; then
-	GIT_CMD=$(command -v chroot-git)
-elif command -v git >/dev/null 2>&1; then
-	GIT_CMD=$(command -v git)
-else
+PATH="/usr/libexec/chroot-git:$PATH"
+if ! command -v git >/dev/null 2>&1; then
 	die "neither chroot-git nor git could be found"
 fi
 
 scan() {
 	rx="$1" msg="$2"
 	template_path=$template
+	maybe_git=
 	if [ "$tip_rev" ]; then
 		template_path="${tip_rev}:${template}"
-		maybe_git="$GIT_CMD"
+		maybe_git="git"
 		revspec="[^:]*:"
 	fi
 	$maybe_git grep -P -Hn -e "$rx" "$template_path" |
@@ -37,7 +35,7 @@ scan() {
 show_template() {
 	rev="$1"
 	if [ "$rev" ]; then
-		$GIT_CMD cat-file blob "${rev}:${template}" 2>/dev/null
+		git cat-file blob "${rev}:${template}" 2>/dev/null
 	else
 		cat "${template}" 2>/dev/null
 	fi