ARM: at91: pm: fix at91rm9200 standby

at91rm9200 standby and suspend to ram has been broken since
00482a40. It is wrongly using AT91_BASE_SYS which is a physical address
and actually doesn't correspond to any register on at91rm9200.

Use the correct at91_ramc_base[0] instead.

Fixes: 00482a40 (ARM: at91: implement the standby function for pm/cpuidle)
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/mach-at91/pm.h

@@ -44,7 +44,7 @@ static inline void at91rm9200_standby(void)
 		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
 		"    str    %5, [%1, %2]"
 		:
-		: "r" (0), "r" (AT91_BASE_SYS), "r" (AT91RM9200_SDRAMC_LPR),
+		: "r" (0), "r" (at91_ramc_base[0]), "r" (AT91RM9200_SDRAMC_LPR),
 		  "r" (1), "r" (AT91RM9200_SDRAMC_SRR),
 		  "r" (lpr));
 }