Apply type-mismatch for gcc-10 to all gcc targets (wrf-model#1848)

TYPE: bug-fix

KEYWORDS: GCC

SOURCE: Stephen Sachs (AWS)

DESCRIPTION OF CHANGES:
Problem:
GCC-10 onwards compilation fails on ARM because of missing macro, FCCOMPAT.

Solution:
In order to patch GCC arguments when using GCC-10+ a line FCCOMPAT is necessary in configure.wrf. This patch is an extension to wrf-model#1251.

Author: stephenmsachs

arch/configure.defaults

@@ -2054,6 +2054,7 @@ FCDEBUG         =       # -g $(FCNOOPT)  # -fbacktrace -ggdb -fcheck=bounds,do,m
 FORMAT_FIXED    =       -ffixed-form
 FORMAT_FREE     =       -ffree-form -ffree-line-length-none
 FCSUFFIX        =
+FCCOMPAT        =
 BYTESWAPIO      =       -fconvert=big-endian -frecord-marker=4
 FCBASEOPTS_NO_G =       -w $(FORMAT_FREE) $(BYTESWAPIO) $(FCCOMPAT)
 FCBASEOPTS      =       $(FCBASEOPTS_NO_G) $(FCDEBUG)