x86/boot: Use proper array element type in memset() size calculation

I changed open coded zeroing loops to explicit memset()s in the
following commit:

5e9ebbd87a99 ("x86/boot: Micro-optimize reset_early_page_tables()")

The base for the size argument of memset was sizeof(pud_p/pmd_p), which
are pointers - but the initialized array has pud_t/pmd_t elements.

Luckily the two types had the same size, so this did not result in any
runtime misbehavior.

Signed-off-by: Alexander Kuleshov <[e-mail]>
Cc: Alexander Popov <[e-mail]>
Cc: Andrey Ryabinin <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Andy Shevchenko <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

arch/x86/kernel/head64.c

···
 		}
 
 		pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
-		memset(pud_p, 0, sizeof(pud_p) * PTRS_PER_PUD);
+		memset(pud_p, 0, sizeof(*pud_p) * PTRS_PER_PUD);
 		*pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
 	}
 	pud_p += pud_index(address);
···
 		}
 
 		pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
-		memset(pmd_p, 0, sizeof(pmd_p) * PTRS_PER_PMD);
+		memset(pmd_p, 0, sizeof(*pmd_p) * PTRS_PER_PMD);
 		*pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
 	}
 	pmd = (physaddr & PMD_MASK) + early_pmd_flags;