asterisk13: add patch from alpine linux to fix AMI on musl

asterisk13: add patch from alpine linux to fix AMI on musl

This adds ASTERISK-24517.patch from alpine linux. Without the patch
there are problems with the tcp/tls wrapper when running on a musl
toolchain. This is visible when toying with AMI:

LEDE*CLI> !nc localhost 5038
[Sep 10 12:13:25] WARNING[10315]: tcptls.c:684 handle_tcptls_connection: FILE * open failed!

This fixes issue #185 for asterisk 13 in trunk. The patch cannot be
applied to asterisk 11.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>