vexpress: Sign up as maintainer

These ARM boards are in nice shape and still being used a lot
with e.g. QEMU, so I can maintain them.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

board/armltd/vexpress/MAINTAINERS

@@ -1,13 +1,9 @@
-VEXPRESS BOARD
-#M:	-
+VERSATILE EXPRESS BOARDS
+M:	Linus Walleij <linus.walleij@linaro.org>
 S:	Maintained
 F:	board/armltd/vexpress/
 F:	include/configs/vexpress_ca15_tc2.h
 F:	configs/vexpress_ca15_tc2_defconfig
-
-VEXPRESS_CA5X2 BOARD
-#M:	Matt Waddel <matt.waddel@linaro.org>
-S:	Orphan (since 2014-08)
 F:	include/configs/vexpress_ca5x2.h
 F:	configs/vexpress_ca5x2_defconfig
 F:	include/configs/vexpress_ca9x4.h