v3d: Use util_upload_index_buffer like other drivers.

Saves some upload boilerplate.
10 jobs for !922 with index-upload in 11 minutes and 23 seconds (queued for 1 second)
latest detached
Status Job ID Name Coverage
  Containers Build
passed #309299
debian

00:00:21

 
  Build+Test
passed #309301
meson-clang

00:10:18

passed #309305
meson-clover

00:11:01

passed #309304
meson-main

00:05:13

passed #309300
meson-swr-glvnd

00:08:15

passed #309306
meson-vulkan

00:02:21

passed #309308
scons-llvm

00:03:40

passed #309307
scons-nollvm

00:06:13

passed #309302
scons-swr

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passed #309303
scons-win64

00:09:49