[ARM] pxa: move pwm.c to common plat-pxa directory

Signed-off-by: Eric Miao <eric.miao@marvell.com>

arch/arm/mach-pxa/Makefile

@@ -15,7 +15,6 @@ endif
 
 # Generic drivers that other drivers may depend upon
 obj-$(CONFIG_PXA_SSP)		+= ssp.o
-obj-$(CONFIG_HAVE_PWM)		+= pwm.o
 
 # SoC-specific code
 obj-$(CONFIG_PXA25x)		+= mfp-pxa2xx.o pxa2xx.o pxa25x.o

arch/arm/plat-pxa/Makefile

@@ -7,3 +7,5 @@ obj-y	:= dma.o
 obj-$(CONFIG_GENERIC_GPIO)	+= gpio.o
 obj-$(CONFIG_PXA3xx)		+= mfp.o
 obj-$(CONFIG_ARCH_MMP)		+= mfp.o
+
+obj-$(CONFIG_HAVE_PWM)		+= pwm.o