All Vulkan command buffers are only submitted once so we can set the
VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT which may help performance.

Bug: angleproject:4304
Change-Id: Ibd116dcac4e78a2c058eb3da54489057d6fa8f44
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2107800Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Charlie Lao <cclao@google.com>
Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>
Commit-Queue: Tobin Ehlis <tobine@google.com>