Fortran on windows not used

[h-vetinari]

Despite the fact that the build script here does

suitesparse-feedstock/recipe/build-one.bat

Lines 3 to 9 in a289ee4

	if "%FC%" NEQ "" (
	echo using fortran %FC%
	set "CMAKE_ARGS=!CMAKE_ARGS! -DSUITESPARSE_HAS_FORTRAN:BOOL=ON"
	) else (
	echo no fortran
	set "CMAKE_ARGS=!CMAKE_ARGS! -DSUITESPARSE_HAS_FORTRAN:BOOL=OFF"
	)

and that FC is set through {{ compiler("fortran") }}, the logs of the build show that this is not recognized:

 │ │ -- Looking for a Fortran compiler
 │ │ -- Looking for a Fortran compiler - NOTFOUND
 │ │ -- Fortran:          not available

Perhaps this is because suitespare doesn't know flang yet.