fold-const.c (fold_convert): Make function extern/public.

fold-const.c (fold_convert): Make function extern/public.

	* fold-const.c (fold_convert): Make function extern/public.
	* tree.h (fold_convert): Prototype here.
	* builtins.c (expand_builtin_strstr, expand_builtin_strchr,
	expand_builtin_strrchr, expand_builtin_strpbrk,
	expand_builtin_mempcpy, expand_builtin_bcopy,
	expand_builtin_bzero, expand_builtin_memcmp,
	expand_builtin_strcmp, expand_builtin_strncmp,
	stabilize_va_list, expand_builtin_sprintf,
	fold_trunc_transparent_mathfn, fold_builtin_logarithm,
	fold_builtin_exponent, fold_builtin_mempcpy,
	fold_builtin_strcpy, fold_builtin_strcmp, fold_builtin_strncmp,
	fold_builtin_signbit, fold_builtin_isdigit, fold_builtin): Prefer
	fold_convert to "convert" or "fold (build1 (NOP_EXPR, ...))".

From-SVN: r80878