* defs.h (xfree, mcalloc, mmalloc, mrealloc, mfree, xmmalloc,

* defs.h (xfree, mcalloc, mmalloc, mrealloc, mfree, xmmalloc,
xmrealloc): Move existing declarations to the one place and
re-order to be consistent.
(xmcalloc, xmfree): Declare.
(xmmalloc, xmrealoc): Assume ISO-C - use size_t and void* in
declaration.

* utils.c (size_t): Delete #ifdef defining size_t.
(mmalloc, mrealloc, mcalloc, mfree): Re-order.
(mmalloc, mrealloc, mcalloc): Document as only calls in GDB
corresponding malloc, realloc, calloc.
(mfree): Call free directly.
(xmmalloc, xmrealloc): Clean up. Assume ISO-C.
(xmcalloc, xmfree): New functions. Copy old xcalloc and xfree
function bodies to here.
(xcalloc, xfree): Call xmcalloc and xmfree respectfully.