drm/nouveau: Improve variable name in nouveau_sched_init()

nouveau_sched_init() uses the function drm_sched_init(). The latter
function has parameters called "hang_limit" and "timeout" in its API
documentation.

nouveau_sched_init(), however, defines a variable called
"job_hang_limit" which is passed to drm_sched_init()'s "timeout"
parameter. The actual "hang_limit" parameter is directly set to 0.

Rename "job_hang_limit" to "timeout".

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240712062618.8057-1-pstanner@redhat.com