Don't duplicate src/osx/cocoa/stdpaths.mm in wxiOS files list

This file is already included in BASE_OSX_SHARED_SRC, which is part of
wxiOS sources, so there is no need to repeat it in OSX_IPHONE_SRC as
well.

This fixes warnings about ignoring duplicate rules in the makefile
in command line builds.

build/bakefiles/files.bkl

@@ -2699,7 +2699,6 @@ IMPORTANT: please read docs/tech/tn0016.txt before modifying this file!
     src/osx/iphone/toolbar.mm
     src/osx/iphone/utils.mm
     src/osx/iphone/window.mm
-    src/osx/cocoa/stdpaths.mm
     src/osx/iphone/settings.mm
     src/osx/sound_osx.cpp
     src/osx/core/sound.cpp

build/cmake/files.cmake

@@ -2552,7 +2552,6 @@ set(OSX_COCOA_HDR
 set(OSX_IPHONE_SRC
     ${OSX_COMMON_SRC}
     src/generic/regiong.cpp
-    src/osx/cocoa/stdpaths.mm
     # iphone files
     src/osx/iphone/anybutton.mm
     src/osx/iphone/button.mm

build/files

@@ -2534,7 +2534,6 @@ OSX_IPHONE_SRC =
     $(OSX_COMMON_SRC)
     src/generic/animateg.cpp
     src/generic/regiong.cpp
-    src/osx/cocoa/stdpaths.mm
     src/osx/core/sound.cpp
     src/osx/iphone/anybutton.mm
     src/osx/iphone/button.mm