This backports a patch from upstream gpgme to fix compilation with glibc 2.34.

It fixes the following build problem:
posix-io.c: In function '_gpgme_io_spawn':
posix-io.c:577:23: error: void value not ignored as it ought to be
  577 |             while ((i = closefrom (fd)) && errno == EINTR)
      |                       ^
make[5]: *** [Makefile:947: posix-io.lo] Error 1

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>