BUG_ON cleanups in arch/i386

This changes a couple of if() BUG(); constructs to
BUG_ON(); so it can be safely optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c
index 90089c1..1674161 100644
--- a/arch/i386/mm/init.c
+++ b/arch/i386/mm/init.c
@@ -569,8 +569,7 @@
 	int bad_ppro;
 
 #ifdef CONFIG_FLATMEM
-	if (!mem_map)
-		BUG();
+	BUG_ON(!mem_map);
 #endif
 	
 	bad_ppro = ppro_with_ram_bug();