Merge branch 'atmosphere/noahmp_no_f2008_flag' into develop (PR #1186)

This merge adds a work-around for Noah-MP compilation issues with the GNU
-std=f2008 flag.

At present, the Noah-MP code fails to compile with the GNU compilers using the
-std=f2008 flag, which is included in the FFLAGS set for the 'gnu' build target:

  RunoffSurfaceDynamicVicMod.F90:205:4:

    151 |                           goto 1003
        |                                   2
  ......
    205 | 1003                if ( DepthYTmp <= 0.0 ) DepthYTmp = 0.0
        |    1
  Error: Legacy Extension: Label at (1) is not in the same block as the GOTO statement at (2)
  RunoffSurfaceDynamicVicMod.F90:205:4:

    175 |                              goto 1003
        |                                      2
  ......
    205 | 1003                if ( DepthYTmp <= 0.0 ) DepthYTmp = 0.0
        |    1
  Error: Legacy Extension: Label at (1) is not in the same block as the GOTO statement at (2)

As a work-around for this issue, this merge adds logic to the Noah-MP Makefile
to remove -std=f2008 if it is present in FFLAGS. The modified FFLAGS are only
used when compiling Noah-MP, and so Fortran 2008 compliance is still enforced
for other code when building with the 'gnu' target.

* atmosphere/noahmp_no_f2008_flag:
  Work around Noah-MP compilation issues with GNU -std=f2008 flag

src/core_atmosphere/physics/physics_noahmp/src/Makefile

@@ -1,5 +1,11 @@
 .SUFFIXES: .F90 .o
 
+#
+# The Noah-MP code fails to build with the GNU compilers with -std=f2008,
+# so remove that flag here if it is present in FFLAGS
+#
+FFLAGS_NONSTD = $(shell printf "%s" "$(FFLAGS)" | sed -e 's/-std=f2008//g' )
+
 all: dummy src
 
 dummy:
@@ -337,5 +343,5 @@ clean:
 	$(RM) *.i
 
 .F90.o:
-	$(FC) $(CPPFLAGS) $(COREDEF) $(FFLAGS) -c $*.F90 $(CPPINCLUDES) $(FCINCLUDES) -I../utility -I../../../../framework
+	$(FC) $(CPPFLAGS) $(COREDEF) $(FFLAGS_NONSTD) -c $*.F90 $(CPPINCLUDES) $(FCINCLUDES) -I../utility -I../../../../framework