Move flag to Compiler/VisualAge-Fortran module

The CMAKE_Fortran_DEFINE_FLAG value applies to the IBM Fortran compilers
on all platforms.  This moves the setting to the platform-independent
compiler information file.

Modules/Compiler/VisualAge-Fortran.cmake

@@ -1 +1,2 @@
 SET(CMAKE_Fortran_VERBOSE_FLAG "-V")
+SET(CMAKE_Fortran_DEFINE_FLAG "-WF,-D")

Modules/Platform/AIX-VisualAge-Fortran.cmake

@@ -1 +0,0 @@
-include(Platform/xlf)

Modules/Platform/Linux-VisualAge-Fortran.cmake

@@ -1,3 +1,2 @@
 SET(CMAKE_SHARED_LIBRARY_C_FLAGS "")        
 SET(CMAKE_SHARED_LIBRARY_LINK_C_FLAGS "")  
-include(Platform/xlf)

Modules/Platform/xlf.cmake

@@ -1 +0,0 @@
-set(CMAKE_Fortran_DEFINE_FLAG "-WF,-D")