Make source file names more consistent

Use platform prefix for files specific to that platform AND that have no
credible alternative API on that platform.

The exception is WinMM, which will be replaced before 3.2.

src/CMakeLists.txt

@@ -12,14 +12,14 @@ set(common_HEADERS internal.h
 set(common_SOURCES context.c init.c input.c monitor.c window.c)
 
 if (_GLFW_COCOA)
-    set(glfw_HEADERS ${common_HEADERS} cocoa_platform.h iokit_joystick.h
+    set(glfw_HEADERS ${common_HEADERS} cocoa_platform.h cocoa_joystick.h
                      posix_tls.h)
-    set(glfw_SOURCES ${common_SOURCES} cocoa_init.m cocoa_monitor.m
-                     cocoa_window.m iokit_joystick.m mach_time.c posix_tls.c)
+    set(glfw_SOURCES ${common_SOURCES} cocoa_init.m cocoa_joystick.m
+                     cocoa_monitor.m cocoa_window.m cocoa_time.c posix_tls.c)
 elseif (_GLFW_WIN32)
-    set(glfw_HEADERS ${common_HEADERS} win32_platform.h winmm_joystick.h)
-    set(glfw_SOURCES ${common_SOURCES} win32_init.c win32_monitor.c win32_time.c
-                     win32_tls.c win32_window.c winmm_joystick.c)
+    set(glfw_HEADERS ${common_HEADERS} win32_platform.h win32_joystick.h)
+    set(glfw_SOURCES ${common_SOURCES} win32_init.c win32_joystick.c
+                     win32_monitor.c win32_time.c win32_tls.c win32_window.c)
 elseif (_GLFW_X11)
     set(glfw_HEADERS ${common_HEADERS} x11_platform.h xkb_unicode.h
                      linux_joystick.h posix_time.h posix_tls.h)

src/cocoa_platform.h

@@ -39,7 +39,7 @@ typedef void* id;
 #endif
 
 #include "posix_tls.h"
-#include "iokit_joystick.h"
+#include "cocoa_joystick.h"
 
 #if defined(_GLFW_NSGL)
  #include "nsgl_context.h"

src/win32_platform.h

@@ -140,7 +140,7 @@ typedef HRESULT (WINAPI * DWMFLUSH_T)(VOID);
 typedef HRESULT (WINAPI * SETPROCESSDPIAWARENESS_T)(PROCESS_DPI_AWARENESS);
 #define _glfw_SetProcessDPIAwareness _glfw.win32.shcore.SetProcessDPIAwareness
 
-#include "winmm_joystick.h"
+#include "win32_joystick.h"
 
 #if defined(_GLFW_WGL)
  #include "wgl_context.h"