avcodec/aarch64/vvc: Optimize apply_bdofHEADmaster

Before this patch, prof_grad_filter calculate
gh[0], gh[1], gv[0], gv[1] and save them to stack.

derive_bdof_vx_vy load them from stack and calculate
gh[0] + gh[1], gv[0] + gv[1].

apply_bdof_min_block load them from stack and calculate
gh[0] - gh[1], gv[0] - gv[1]

This patch add bdof_grad_filter, which calculate gh[0] + gh[1],
gh[0] - gh[1], gv[0] + gv[1], gv[0] - gv[1], and save them to
stack, so derive_bdof_vx_vy and apply_bdof_min_block can use the
results directly.

prof_grad_filter is kept for reuse by other functions in the future.

Benchmark on rpi5 with gcc 12
                               Before               After
--------------------------------------------------------------------
apply_bdof_8_8x16_c:       |   7431.4 ( 1.00x)   |   7371.7 ( 1.00x)
apply_bdof_8_8x16_neon:    |   1175.4 ( 6.32x)   |   1036.3 ( 7.11x)
apply_bdof_8_16x8_c:       |   7182.2 ( 1.00x)   |   7201.1 ( 1.00x)
apply_bdof_8_16x8_neon:    |   1021.7 ( 7.03x)   |    879.9 ( 8.18x)
apply_bdof_8_16x16_c:      |  14577.1 ( 1.00x)   |  14589.3 ( 1.00x)
apply_bdof_8_16x16_neon:   |   2012.8 ( 7.24x)   |   1743.3 ( 8.37x)
apply_bdof_10_8x16_c:      |   7292.4 ( 1.00x)   |   7308.5 ( 1.00x)
apply_bdof_10_8x16_neon:   |   1156.3 ( 6.31x)   |   1045.3 ( 6.99x)
apply_bdof_10_16x8_c:      |   7112.4 ( 1.00x)   |   7214.4 ( 1.00x)
apply_bdof_10_16x8_neon:   |   1007.6 ( 7.06x)   |    904.8 ( 7.97x)
apply_bdof_10_16x16_c:     |  14363.3 ( 1.00x)   |  14476.4 ( 1.00x)
apply_bdof_10_16x16_neon:  |   1986.9 ( 7.23x)   |   1783.1 ( 8.12x)
apply_bdof_12_8x16_c:      |   7433.3 ( 1.00x)   |   7374.7 ( 1.00x)
apply_bdof_12_8x16_neon:   |   1155.9 ( 6.43x)   |   1040.8 ( 7.09x)
apply_bdof_12_16x8_c:      |   7171.1 ( 1.00x)   |   7376.3 ( 1.00x)
apply_bdof_12_16x8_neon:   |   1010.8 ( 7.09x)   |    899.4 ( 8.20x)
apply_bdof_12_16x16_c:     |  14515.5 ( 1.00x)   |  14731.5 ( 1.00x)
apply_bdof_12_16x16_neon:  |   1988.4 ( 7.30x)   |   1785.2 ( 8.25x)

0 files changed, 0 insertions, 0 deletions