sparc: Fix build with DEBUG_PAGEALLOC enabled.

arch/sparc/mm/init_64.c:1622:22: error: unused variable '__swapper_4m_tsb_phys_patch_end' [-Werror=unused-variable]
arch/sparc/mm/init_64.c:1621:22: error: unused variable '__swapper_4m_tsb_phys_patch' [-Werror=unused-variable]

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index adfac23..581531d 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1618,18 +1618,20 @@
 {
 	extern unsigned int __swapper_tsb_phys_patch;
 	extern unsigned int __swapper_tsb_phys_patch_end;
-	extern unsigned int __swapper_4m_tsb_phys_patch;
-	extern unsigned int __swapper_4m_tsb_phys_patch_end;
 	unsigned long ktsb_pa;
 
 	ktsb_pa = kern_base + ((unsigned long)&swapper_tsb[0] - KERNBASE);
 	patch_one_ktsb_phys(&__swapper_tsb_phys_patch,
 			    &__swapper_tsb_phys_patch_end, ktsb_pa);
 #ifndef CONFIG_DEBUG_PAGEALLOC
+	{
+	extern unsigned int __swapper_4m_tsb_phys_patch;
+	extern unsigned int __swapper_4m_tsb_phys_patch_end;
 	ktsb_pa = (kern_base +
 		   ((unsigned long)&swapper_4m_tsb[0] - KERNBASE));
 	patch_one_ktsb_phys(&__swapper_4m_tsb_phys_patch,
 			    &__swapper_4m_tsb_phys_patch_end, ktsb_pa);
+	}
 #endif
 }