util/lint: exclude patch files from asm syntax check

This allows the paches to add cross-compile support for true x86 16-bit
GCC (ia16) to go in.

Change-Id: If9246b5fb2f3578afea601fd63b7d716ddf8597e
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/19714
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

util/lint/lint-stable-010-asm-syntax

@@ -15,4 +15,4 @@
 # DESCR: Check that we use a single assembler syntax
 
 LC_ALL=C export LC_ALL
-git grep -n "\.\(att\|intel\)_syntax\>"
+git grep -n "\.\(att\|intel\)_syntax\>" | grep -v '\.patch:'