drm/i915: Don't set enabled value of all CRTCs when restoring the mode

The code in intel_crtc_restore_mode() sets the enabled value of all the
CRTCs when restoring the mode after a suspend/resume cycle. When more
than one CRTC is enabled, that causes drm_atomic_helper_check_modeset()
to fail if there is more than one pipe enabled, since all but one CRTC
has valid connector data. Instead, set only the enabled value for the
CRTC passed as an argument.

v2: Don't leak atomic state. (Matt)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=90468
References: https://bugs.freedesktop.org/show_bug.cgi?id=90396


Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>