[POWERPC] Spelling fixes: arch/ppc/

Spelling fixes in arch/ppc/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/ppc/mm/init.c b/arch/ppc/mm/init.c
index c374e53..390dd19 100644
--- a/arch/ppc/mm/init.c
+++ b/arch/ppc/mm/init.c
@@ -48,7 +48,7 @@
 #include "mmu_decl.h"
 
 #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
-/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
+/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
 #if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
 #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
 #endif