metal: fix regression when no metal devices are present Otherwise, metal initialization segfaults. This situation was fixed before in acd38efee316f3a5ed2e6afcbc5814807c347053. Regression was introduced in bf9087f59aab940cf312b85a67067ce33d9e365a.
metal: fix regression when no metal devices are present Otherwise, metal initialization segfaults. This situation was fixed before in acd38efee316f3a5ed2e6afcbc5814807c347053. Regression was introduced in bf9087f59aab940cf312b85a67067ce33d9e365a.