ARM: s5p64x0: avoid build warning for uncompress.h

Commit 5336539 "ARM: S5P64X0: Use common uncompress.h part
for plat-samsung" was missing a type cast, this brings
it in line with the other samsung platforms.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/mach-s5p64x0/include/mach/uncompress.h

@@ -23,9 +23,9 @@ static void arch_detect_cpu(void)
 	chipid = *(const volatile unsigned int __force *) 0xE0100118;
 
 	if ((chipid & 0xff000) == 0x50000)
-		uart_base = S5P6450_PA_UART(CONFIG_S3C_LOWLEVEL_UART_PORT);
+		uart_base = (volatile u8 *)S5P6450_PA_UART(CONFIG_S3C_LOWLEVEL_UART_PORT);
 	else
-		uart_base = S5P6440_PA_UART(CONFIG_S3C_LOWLEVEL_UART_PORT);
+		uart_base = (volatile u8 *)S5P6440_PA_UART(CONFIG_S3C_LOWLEVEL_UART_PORT);
 
 	fifo_mask = S3C2440_UFSTAT_TXMASK;
 	fifo_max = 63 << S3C2440_UFSTAT_TXSHIFT;