MAINTAINERS: ghes_edac: update pattern

Commit 77c5f5d2 ("ghes_edac: Register at EDAC core the BIOS report")
typoed the file pattern.  Fix it.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>