builtin-sprintf-warn-1.c: Cast 0 to wint_t to placate -Wformat on targets...

builtin-sprintf-warn-1.c: Cast 0 to wint_t to placate -Wformat on targets where the type is not int.

gcc/testsuite/Changelog:
	* gcc.dg/tree-ssa/builtin-sprintf-warn-1.c: Cast 0 to wint_t
	to placate -Wformat on targets where the type is not int.

From-SVN: r241123