ARM: pxa: fix various compilation problems

Due to commit 88f718e3
"ARM: pxa: delete the custom GPIO header" some drivers fail
compilation, for example like this:

In file included from sound/soc/pxa/spitz.c:28:0:
sound/soc/pxa/spitz.c: In function ‘spitz_ext_control’:
arch/arm/mach-pxa/include/mach/spitz.h:111:30: error:
‘PXA_NR_BUILTIN_GPIO’ undeclared (first use in this function)
 #define SPITZ_SCP_GPIO_BASE (PXA_NR_BUILTIN_GPIO)
(etc.)

This is caused by implicit inclusion of <mach/irqs.h> from
various board-specific headers under <mach/*> in the PXA
platform. So we take a sweep over these, and for every such
header that uses PXA_NR_BUILTIN_GPIO or PXA_GPIO_TO_IRQ()
we explicitly #include "irqs.h" so that we satisfy the
dependency in the board include file alone.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Kevin Hilman <khilman@linaro.org>