bms: convert to CFLAGS_MODULE Upstream has removed the support for EXTRA_CFLAGS in [1]. The driver here is converted to use CFLAGS_MODULE as a direct replacement. No functional changes expected from this patch. Bug: 412122604 Link: https://git.kernel.org/torvalds/c/e966ad0edd00 [1] Change-Id: Ib76c03a266c6e5ef49963473e10e8057775a3253 Signed-off-by: Carlos Llamas <[email protected]>