package/dvb-apps: fix build failure with glibc 2.31

package/dvb-apps: fix build failure with glibc 2.31

dvb-apps fails to build with glibc 2.31 with the following error:
| dvbdate.c: In function set_time:
| dvbdate.c:312:6: warning: implicit declaration of function stime; did you mean ctime? [-Wimplicit-function-declaration]
| 312 | if (stime(new_time)) {
| | ^~~~~
| | ctime

Fixes:

http://autobuild.buildroot.net/results/95f30c5e6af2274418bb44a20da7caac69f1dd68/

references:
1. https://gitweb.gentoo.org/repo/gentoo.git/commit/media-tv/linuxtv-dvb-apps/files/linuxtv-dvb-apps-glibc-2.31.patch?id=eb705f892eae45b93306c1de1407c1c22ac23956
2. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=964223

Signed-off-by: Dagg Stompler <daggs@gmx.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>