AT91: atmel_pwm only available for certain AT91 processors

Only three of Atmel's AT91 processors (SAM9263, SAM9RL and CAP9) include a
PWM controller.

It should therefore only be possible to enable the misc/atmel_pwm.c driver
on those processors (and not all AT91 processors).
Signed-off-by: Andrew Victor <linux@maxim.org.za>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/Kconfig

@@ -15,7 +15,7 @@ if MISC_DEVICES
 
 config ATMEL_PWM
 	tristate "Atmel AT32/AT91 PWM support"
-	depends on AVR32 || ARCH_AT91
+	depends on AVR32 || ARCH_AT91SAM9263 || ARCH_AT91SAM9RL || ARCH_AT91CAP9
 	help
 	  This option enables device driver support for the PWM channels
 	  on certain Atmel prcoessors.  Pulse Width Modulation is used for