MAINTAINERS: fix Colibri PXA270 file pattern

The original commit 403d2971 ("pxa/income: Add Income SBC support")
started with the wrong file pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>