c: Set attributes for fields when forming a composite type [PR117806]

c: Set attributes for fields when forming a composite type [PR117806]

We need to call decl_attributes when creating the fields for a composite
type.

	PR c/117806

gcc/c/ChangeLog:
	* c-typeck.cc (composite_type_internal): Call decl_attributes.

gcc/testsuite/ChangeLog:
	* gcc.dg/pr117806.c: New test.

(cherry picked from commit 1539bcd19c5928d8359722c532dfcc7a26a16dda)