coarray_43.f90: Add "-latomic" option if libatomic_available.

	* gfortran.dg/coarray_43.f90: Add "-latomic" option if
	libatomic_available.

From-SVN: r245182

gcc/testsuite/ChangeLog

 2017-02-03  John David Anglin  <danglin@gcc.gnu.org>
 
+	* gfortran.dg/coarray_43.f90: Add "-latomic" option if
+	libatomic_available.
+
 	* gcc.dg/pr77587.c: Require alias support.
 	* gcc.dg/pr77587a.c: Likewise.
 

gcc/testsuite/gfortran.dg/coarray_43.f90

 ! { dg-do link }
 ! { dg-options "-fcoarray=lib -lcaf_single" }
+! { dg-additional-options "-latomic" { target libatomic_available } }
 
 program coarray_43
   implicit none