Warning: implicit declaration of function 'set_region_range' is invalid in C99

[sam-ellis]

When compiling oink on Mac OS X using Apple LLVM version 8.0.0 (clang-800.0.38) the following warning is seen:

gcc -c -o regions.o -I.. -iquote  -DNMEMDEBUG -DSIZEOF_VOIDP=4 -Wall -g -O2 regions.c
In file included from regions.c:288:
../libregion/pages.c:270:3: warning: implicit declaration of function 'set_region_range' is invalid in C99 [-Wimplicit-function-declaration]
  set_region_range(newp, (char *)newp + request_bytes, FREEPAGE);
  ^