powerpc/book3s/mmu-hash.h: delete duplicated word

Drop the repeated word "below".
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200726003809.20454-2-rdunlap@infradead.org

arch/powerpc/include/asm/book3s/64/mmu-hash.h

@@ -793,7 +793,7 @@ static inline unsigned long get_vsid(unsigned long context, unsigned long ea,
 }
 
 /*
- * For kernel space, we use context ids as below
+ * For kernel space, we use context ids as
  * below. Range is 512TB per context.
  *
  * 0x00001 -  [ 0xc000000000000000 - 0xc001ffffffffffff]