grab fix from glibc:

2005-11-18  Paul Brook  <paul@codesourcery.com>

	* sysdeps/unix/sysv/linux/m68k/bits/mman.h: Add definition of
	MREMAP_FIXED.

libc/sysdeps/linux/m68k/bits/mman.h

@@ -72,4 +72,5 @@
 /* Flags for `mremap'.  */
 #ifdef __USE_GNU
 # define MREMAP_MAYMOVE	1
+# define MREMAP_FIXED	2
 #endif