ARM: OMAP: Fixed comments on global PRM register usage

Fixed comments on global PRM register usage.
Signed-off-by: NKalle Jokiniemi <ext-kalle.jokiniemi@nokia.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/prm.h

@@ -30,7 +30,7 @@
 
 /*
  * Architecture-specific global PRM registers
- * Use prm_{read,write}_reg() with these registers.
+ * Use __raw_{read,write}l() with these registers.
  *
  * With a few exceptions, these are the register names beginning with
  * PRCM_* on 24xx, and PRM_* on 34xx.  (The exceptions are the