Making kpatch-build compatible with custom gcc names

After changing the gcc name in a linux tree to gcc72, kpatch-build failed to
produce hotpatches with the error message "ERROR: no changed objects found."

This is due to a wrapper script called kpatch-gcc, called while kpatch-build
builds the kernel, which checks if the compiler name matches exactly gcc,
failing the check when comparing to gcc72, and thus not producing the expected
file changed_objs containing the list of changed objects.

This commit fixes this issue by loosening the check on the gcc name.

Signed-off-by: Bruno Loreto <loretob@amazon.com>
Reviewed-by: Bjoern Doebel <doebel@amazon.com>
Reviewed-by: Amit Shah <aams@amazon.com>
Reviewed-by: Pawel Wieczorkiewicz <wipawel@amazon.com>

kpatch-build/kpatch-gcc

@@ -13,7 +13,7 @@ fi
 
 declare -a args=("$@")
 
-if [[ "$TOOLCHAINCMD" = "gcc" ]] ; then
+if [[ "$TOOLCHAINCMD" =~ "gcc" ]] ; then
 	while [ "$#" -gt 0 ]; do
 		if [ "$1" = "-o" ]; then
 			obj="$2"