This is a straight replacement of "calls we can clobber without saving
them first".

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* shrink-wrap.c: Include function-abi.h.
	(requires_stack_frame_p): Use crtl->abi to test whether the
	current function can use a register without saving it first.

From-SVN: r276337