Support Arm Compiler for Linux as classic flang (#4436)

* Support ArmCompilerforLinux as classic flang

f_check

@@ -45,7 +45,7 @@ if [ -z "$compiler" ]; then
 	      pathf90 pathf95
 	      pgf95 pgf90 pgf77 pgfortran nvfortran
 	      flang egfortran
-              ifort nagfor ifx ftn crayftn"
+              ifort nagfor ifx ftn crayftn armflang"
 
     for list in $lists; do
         for p in $path; do
@@ -86,6 +86,10 @@ else
 		vendor=CRAY
 		openmp='-fopenmp'
 		;;
+   	    *Arm\ F90*)
+		vendor=FLANG
+		openmp='-fopenmp'
+		;;	
             *GNU*|*GCC*)
 
                 v="${data#*GCC: *\) }"