Do not emit a redundant DW_TAG_lexical_block for inlined subroutines

Do not emit a redundant DW_TAG_lexical_block for inlined subroutines

While this already works correctly for the case when an inlined
subroutine contains only one subrange, a redundant DW_TAG_lexical_block
is still emitted when the subroutine has multiple blocks.

Fixes: ac02e5b75451 ("re PR debug/37801 (DWARF output for inlined functions
                      doesn't always use DW_TAG_inlined_subroutine)")

gcc/ChangeLog:

	PR debug/87440
	* dwarf2out.cc (gen_inlined_subroutine_die): Handle the case
	of multiple subranges correctly.

gcc/testsuite/ChangeLog:

	* gcc.dg/debug/dwarf2/inline7.c: New test.