Merge pull request #333 from mlee03/acc2gpu_fix

Fix gpu compile error from PR #328

Author: mlee03

configure.ac

@@ -86,8 +86,8 @@ AM_CONDITIONAL([WITH_MPI], [test x"$build_mpi" = x"yes"])
 AM_CONDITIONAL([WITH_MPI_TESTS], [test x"$build_mpi" = x"yes" -a -z "$SKIP_MPI_TEST"])
 
 #Build with OpenACC suport.  Default is 'no'
-AC_ARG_ENABLE([acc],
-            [AS_HELP_STRING([--enable-acc],
+AC_ARG_ENABLE([gpu],
+            [AS_HELP_STRING([--enable-gpu],
                             [Builds with OpenACC. This will result in a second executable for fregrid, fregrid_gpu.(default no)])])
 AS_IF([test ${enable_gpu:-no} = yes],
       [enable_gpu=yes],