powerpc/ptdump: Fix W+X verification call in mark_rodata_ro()

ptdump_check_wx() also have to be called when pages are mapped
by blocks.

Fixes: 453d87f6a8 ("powerpc/mm: Warn if W+X pages found on boot")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/37517da8310f4457f28921a4edb88fb21d27b62a.1578989531.git.christophe.leroy@c-s.fr

arch/powerpc/mm/pgtable_32.c

@@ -218,6 +218,7 @@ void mark_rodata_ro(void)
 
 	if (v_block_mapped((unsigned long)_sinittext)) {
 		mmu_mark_rodata_ro();
+		ptdump_check_wx();
 		return;
 	}