Fix service_idle_exit build issue with -Werror=maybe-unitialized

[OdyX]

There's only one line that makes the build fail under -Werror=maybe-unitialized :

Compiling listen.c...
cc  -fPIC -g -fstack-protector -D_GNU_SOURCE -I.. -D_CUPS_SOURCE -isystem /usr/include/mit-krb5 -Wdate-time -D_FORTIFY_SOURCE=2 -isystem /usr/include/mit-krb5 -g -O2 -fdebug-prefix-map=/tmp/reprotest.wwqjgR/const_build_path=. -specs=/usr/share/dpkg/no-pie-compile.specs -fstack-protector-strong -Wformat -Werror=format-security -I/usr/include/libusb-1.0 -I/usr/include/dbus-1.0 -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -DDBUS_API_SUBJECT_TO_CHANGE -D_FORTIFY_SOURCE=2 -D_REENTRANT -I/usr/include/p11-kit-1 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_THREAD_SAFE -D_REENTRANT  -Werror -Wno-error=deprecated-declarations -Wall -Wno-format-y2k -Wunused -Wno-unused-result -Wsign-conversion -Wno-format-truncation -Wno-tautological-compare -c -o listen.o listen.c
main.c: In function ‘main’:
main.c:942:14: error: ‘service_idle_exit’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
     if (!fds && service_idle_exit)
              ^~

It should be initialized to 0, right?

[michaelrsweet]

Gotta love GCC for being honest about not being sure about their warnings... :/

Initializing service_idle_exit to 0 is a safe enough, if unnecessary, change.