gspawn: Rename gspawn.c to gspawn-posix.c

This is the first step towards separating the API documentation and
introspection annotations from the platform-specific implementation, so
we can guarantee that the APIs make it into `GLib-2.0.gir` regardless of
which platform the GIR is built on.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>

Helps: #3399

glib/meson.build

@@ -371,7 +371,7 @@ if host_system == 'windows'
     glib_sources += files('dirent/wdirent.c')
   endif
 else
-  glib_sources += files('glib-unix.c', 'gspawn.c', 'giounix.c')
+  glib_sources += files('glib-unix.c', 'gspawn-posix.c', 'giounix.c')
   platform_deps = []
 endif
 

po/POTFILES.in

@@ -198,7 +198,7 @@ glib/gmarkup.c
 glib/goption.c
 glib/gregex.c
 glib/gshell.c
-glib/gspawn.c
+glib/gspawn-posix.c
 glib/gspawn-private.h
 glib/gspawn-win32.c
 glib/gstrfuncs.c