build: restrict MSVC static libs to .lib only

The MSVC linker can now apparently link MinGW .a static libs too, and
StrawberryPerl pollutes the build with its own.

Set CMAKE_FIND_LIBRARY_SUFFIXES to .lib only when MSVC is true for
static builds.

Signed-off-by: Rafael Kitover <rkitover@gmail.com>

CMakeLists.txt

@@ -118,7 +118,9 @@ if(VBAM_STATIC)
     set_property(GLOBAL PROPERTY LINK_SEARCH_START_STATIC ON)
     set_property(GLOBAL PROPERTY LINK_SEARCH_END_STATIC   ON)
 
-    if(NOT MSVC)
+    if(MSVC)
+        set(CMAKE_FIND_LIBRARY_SUFFIXES .lib)
+    else()
         list(INSERT CMAKE_FIND_LIBRARY_SUFFIXES 0 .a)
     endif()
 endif()

cmake/FindSDL2.cmake

@@ -102,8 +102,8 @@ FIND_PATH(SDL2_INCLUDE_DIR SDL.h
 SET(CURRENT_FIND_LIBRARY_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES})
 
 if(SDL2_STATIC)
-    if(WIN32)
-	set(CMAKE_FIND_LIBRARY_SUFFIXES .lib .a)
+    if(MSVC)
+	set(CMAKE_FIND_LIBRARY_SUFFIXES .lib)
     else()
 	set(CMAKE_FIND_LIBRARY_SUFFIXES .a)
     endif()