drivers/misc: Add module.h to files who are really modular.

These files really need the full module.h header file present, but
were just getting it implicitly before.  Fix it up in advance so we
avoid build failures once the cleanup commit is present.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/misc/ab8500-pwm.c b/drivers/misc/ab8500-pwm.c
index 3590315..2208a9d 100644
--- a/drivers/misc/ab8500-pwm.c
+++ b/drivers/misc/ab8500-pwm.c
@@ -10,6 +10,7 @@
 #include <linux/pwm.h>
 #include <linux/mfd/ab8500.h>
 #include <linux/mfd/abx500.h>
+#include <linux/module.h>
 
 /*
  * PWM Out generators