Fix entry points check for VK_KHR_draw_indirect_count

Fix entry points check for VK_KHR_draw_indirect_count

VK_KHR_draw_indirect_count was promoted to core in Vulkan 1.2, but its
non-KHR entry points (vkCmdDrawIndirectCount and
vkCmdDrawIndexedIndirectCount) are not mandatory unless the device
supports the extension. In that case, the drawIndirectCount feature bit
will also be true. Any of the two checks is valid.

Affected tests:
dEQP-VK.api.version_check.entry_points

VK-GL-CTS issue: 3679
Components: Vulkan

Change-Id: I95666c1a22bed7da33f58a50307294c4048cd8ff