Allow subpasses to use secondary command buffers
Allow subpasses to use secondary command buffers

Bug: b/118619338
Test: dEQP-VK.*secondary_cmd_buf*
Change-Id: I46e69e216ae4cc0a8e907692dfce270e11b690a2
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/28129
Tested-by: Chris Forbes <c3279c50043e18e9442c1ae071cafa0e7a4ca967@google.com>
Presubmit-Ready: Chris Forbes <c3279c50043e18e9442c1ae071cafa0e7a4ca967@google.com>
Reviewed-by: Nicolas Capens <51edc787c30f24c4904e8ffbb5523c3a9f7a451d@google.com>

bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader,google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader