[contrib][linux-kernel] Add standard warnings and -Werror to CI

Test the kernel build with the standard warnings enabled so that we
don't miss issues like fixed in PR #2802.

Stacked on top of PR #2802 so CI passes, so it includes the fix. But, I
won't merge until it is merged, so @solbjorn gets the credit for the
fix.

lib/decompress/huf_decompress.c

@@ -47,7 +47,9 @@
  * Disable when MSAN is enabled.
  */
 #if defined(__linux__) || defined(__linux) || defined(__APPLE__)
-# if ZSTD_MEMORY_SANITIZER || ZSTD_DATAFLOW_SANITIZER
+# if ZSTD_MEMORY_SANITIZER
+#  define HUF_ASM_SUPPORTED 0
+# elif ZSTD_DATAFLOW_SANITIZER
 #  define HUF_ASM_SUPPORTED 0
 # else
 #  define HUF_ASM_SUPPORTED 1