ARM: AM33XX: Fix typo that causes an AM duplication in CPU name.

Just fix a typo displaying the CPU info. With CONFIG_DISPLAY_INFO we see
something like AMAM335X-GP rev 0 instead of AM335X-GP rev 0.

Signed-off-by: Enric Balletbo i Serra <eballetbo@iseebcn.com>
Reviewed-by: Javier Martinez Canillas <javier@dowhile0.org>

arch/arm/cpu/armv7/am33xx/sys_info.c

@@ -120,7 +120,7 @@ int print_cpuinfo(void)
 		sec_s = "?";
 	}
 
-	printf("AM%s-%s rev %d\n",
+	printf("%s-%s rev %d\n",
 			cpu_s, sec_s, get_cpu_rev());
 
 	/* TODO: Print ARM and DDR frequencies  */