* libbfd-in.h: Remove alloca cruft. It was missing some necessary

	* libbfd-in.h: Remove alloca cruft.  It was missing some necessary
	cruft (like the #pragma alloca for AIX).
	In addition to that problem, the C alloca calls xmalloc, which
	means checking for being out of memory can't work right.  The
	following changes remove all uses of alloca from BFD.
	* hosts/solaris2.h: Remove alloca cruft.
	* som.c: Replace alloca with a fixed size auto array.
	* aoutx.h, elfcode.h, nlmcode.h, bout.c, coff-alpha.c, ecoff.c,
	ecofflink.c, elf32-hppa.c, elf32-mips.c, linker.c, reloc.c, som.c:
	Replace alloca with malloc and appropriate error checking and
	freeing.
	* linker.c: Replace alloca with obstack_alloc.
	* libbfd.h: Rebuilt.