[Ada] Crash with Inline_Always on a function with an extended return

[Ada] Crash with Inline_Always on a function with an extended return

This patch fixes a crash on a unit with a function with the GNAT-specific
Inline_Always pragma whose body is an extended return statement, when compiling
with no optimization level specified.

2018-06-11  Ed Schonberg  <schonberg@adacore.com>

gcc/ada/

	* inline.adb (Expand_Inlined_Call): If no optimization level is
	specified, the expansion of a call to an Inline_Always function is
	fully performed in the front-end even on a target that support back-end
	inlining.

gcc/testsuite/

	* gnat.dg/inline_always1.adb: New testcase.

From-SVN: r261402