sigrok-cross-mingw: Patch MXE's glib to fix compiler warnings.

sigrok-cross-mingw: Patch MXE's glib to fix compiler warnings.

This fixes parts of bug #986.

This seems to have been fixed upstream recently:
https://gitlab.gnome.org/GNOME/glib/commit/3d7cde654c4c6f3bdad32f5521f28f5802a7c377

Until MXE uses a recent enough glib, we're applying a similar (ported) patch.

This fixes the following compiler warnings:

  src/usb.c: In function 'usb_pollfd_removed':
  src/usb.c:34:20: warning: format '%i' expects argument of type 'int', but argument 3 has type 'long long int' [-Wformat=]
   #define LOG_PREFIX "usb"
                      ^
  src/libsigrok-internal.h:764:41: note: in expansion of macro 'LOG_PREFIX'
   #define sr_err(...) sr_log(SR_LOG_ERR,  LOG_PREFIX ": " __VA_ARGS__)
                                           ^
  src/usb.c:222:2: note: in expansion of macro 'sr_err'
    sr_err("FD to be removed (%" G_GINTPTR_FORMAT
    ^

  src/input/input.c: In function 'sr_input_free':
  src/input/input.c:29:20: warning: format '%u' expects argument of type 'unsigned int', but argument 3 has type 'gsize {aka long long unsigned int}' [-Wformat=]
   #define LOG_PREFIX "input"
                      ^
  ./src/libsigrok-internal.h:763:42: note: in expansion of macro 'LOG_PREFIX'
   #define sr_warn(...) sr_log(SR_LOG_WARN, LOG_PREFIX ": " __VA_ARGS__)
                                            ^
  src/input/input.c:686:3: note: in expansion of macro 'sr_warn'
     sr_warn("Found %" G_GSIZE_FORMAT
     ^

  src/output/analog.c: In function 'receive':
  src/output/analog.c:118:34: warning: format '%u' expects argument of type 'unsigned int', but argument 3 has type 'guint64 {aka long long unsigned int}' [-Wformat=]
       g_string_append_printf(*out, "%"
                                    ^

  src/scpi/scpi.c: In function 'sr_scpi_get_string':
  src/scpi/scpi.c:28:20: warning: format '%u' expects argument of type 'unsigned int', but argument 4 has type 'gsize {aka long long unsigned int}' [-Wformat=]
   #define LOG_PREFIX "scpi"
                      ^
  ./src/libsigrok-internal.h:760:42: note: in expansion of macro 'LOG_PREFIX'
   #define sr_spew(...) sr_log(SR_LOG_SPEW, LOG_PREFIX ": " __VA_ARGS__)
                                            ^
  src/scpi/scpi.c:623:2: note: in expansion of macro 'sr_spew'
    sr_spew("Got response: '%.70s', length %" G_GSIZE_FORMAT ".",
    ^

  In file included from session.c:22:0:
  session.c: In function 'srd_session_metadata_set':
  session.c:190:10: warning: format '%u' expects argument of type 'unsigned int', but argument 4 has type 'guint64 {aka long long unsigned int}' [-Wformat=]
    srd_dbg("Setting session %d samplerate to %"G_GUINT64_FORMAT".",
            ^
  libsigrokdecode-internal.h:101:44: note: in definition of macro 'srd_dbg'
   #define srd_dbg(...) srd_log(SRD_LOG_DBG,  __VA_ARGS__)
                                              ^