package/mesa3d: disable v3d support for arm if neon is not supported

package/mesa3d: disable v3d support for arm if neon is not supported

The v3d driver for arm uses neon instructions unconditionally, so
depend on BR2_ARM_CPU_HAS_NEON.

Fixes:

  http://autobuild.buildroot.net/results/66c4df4ee84b73160dde5fe4437b5abdbd2b50d2

  [1050/1079] Compiling C object 'src/gallium/drivers/v3d/99241e4@@v3d_neon@sta/v3d_tiling.c.o'.
  {standard input}: Assembler messages:
  {standard input}:417: Error: selected processor does not support `vldm r6,{q0,q1,q2,q3}' in ARM mode
  {standard input}:418: Error: selected processor does not support `vst1.8 d0,[r4],r5' in ARM mode
  {standard input}:419: Error: selected processor does not support `vst1.8 d1,[r4],r5' in ARM mode
  {standard input}:420: Error: selected processor does not support `vst1.8 d2,[r4],r5' in ARM mode
  {standard input}:421: Error: selected processor does not support `vst1.8 d3,[r4],r5' in ARM mode
  {standard input}:422: Error: selected processor does not support `vst1.8 d4,[r4],r5' in ARM mode
  {standard input}:423: Error: selected processor does not support `vst1.8 d5,[r4],r5' in ARM mode
  {standard input}:424: Error: selected processor does not support `vst1.8 d6,[r4],r5' in ARM mode

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>