powerpc/book3e: Clarify HW table walk enable/disable message

Before if we didn't support or enable HW table walk we'd get a messaage
like:

MMU: Book3E Page Tables Disabled

Which is a bit misleading.  Now it will say:

MMU: Book3E HW tablewalk not supported
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/mm/tlb_nohash.c

@@ -473,8 +473,8 @@ static void setup_mmu_htw(void)
 			     (unsigned long)&exc_instruction_tlb_miss_htw_book3e, 0);
 		book3e_htw_enabled = 1;
 	}
-	pr_info("MMU: Book3E Page Tables %s\n",
-		book3e_htw_enabled ? "Enabled" : "Disabled");
+	pr_info("MMU: Book3E HW tablewalk %s\n",
+		book3e_htw_enabled ? "enabled" : "not supported");
 }
 
 /*