define mem_info struct before we use it in a prototype

--- include/asm-m68k/setup.h
+++ include/asm-m68k/setup.h
@@ -360,14 +360,14 @@
 #define COMMAND_LINE_SIZE	CL_SIZE
 
 #ifndef __ASSEMBLY__
-extern int m68k_num_memory;		/* # of memory blocks found (and used) */
-extern int m68k_realnum_memory;		/* real # of memory blocks found */
-extern struct mem_info m68k_memory[NUM_MEMINFO];/* memory description */
-
 struct mem_info {
 	unsigned long addr;		/* physical address of memory chunk */
 	unsigned long size;		/* length of memory chunk (in bytes) */
 };
+
+extern int m68k_num_memory;		/* # of memory blocks found (and used) */
+extern int m68k_realnum_memory;		/* real # of memory blocks found */
+extern struct mem_info m68k_memory[NUM_MEMINFO];/* memory description */
 #endif
 
 #endif /* __KERNEL__ */