avcodec/ac3: Remove unused fixed-point ARMv7 DSP

This diff removes 4 unused ARMv7 NEON fixed-point DSP functions.

The function were originally moved here by 4958f35a2 (Dec 2013).

After 9e05421db (Jan 2021), as part of the refactor of the AC3
DSP to consistently use 32-bit sample format in the encoder, these
functions were removed from the DSP function table, but the ARMv7
implementations were kept.

Signed-off-by: Geoff Hill <geoff@geoffhill.org>

libavcodec/arm/ac3dsp_neon.S

@@ -20,25 +20,6 @@
 
 #include "libavutil/arm/asm.S"
 
-function ff_ac3_max_msb_abs_int16_neon, export=1
-        vmov.i16        q0,  #0
-        vmov.i16        q2,  #0
-1:      vld1.16         {q1},     [r0,:128]!
-        vabs.s16        q1,  q1
-        vld1.16         {q3},     [r0,:128]!
-        vabs.s16        q3,  q3
-        vorr            q0,  q0,  q1
-        vorr            q2,  q2,  q3
-        subs            r1,  r1,  #16
-        bgt             1b
-        vorr            q0,  q0,  q2
-        vorr            d0,  d0,  d1
-        vpmax.u16       d0,  d0,  d0
-        vpmax.u16       d0,  d0,  d0
-        vmov.u16        r0,  d0[0]
-        bx              lr
-endfunc
-
 function ff_ac3_exponent_min_neon, export=1
         cmp             r1,  #0
         it              eq
@@ -59,27 +40,6 @@ function ff_ac3_exponent_min_neon, export=1
         pop             {pc}
 endfunc
 
-function ff_ac3_lshift_int16_neon, export=1
-        vdup.16         q0,  r2
-1:      vld1.16         {q1},     [r0,:128]
-        vshl.s16        q1,  q1,  q0
-        vst1.16         {q1},     [r0,:128]!
-        subs            r1,  r1,  #8
-        bgt             1b
-        bx              lr
-endfunc
-
-function ff_ac3_rshift_int32_neon, export=1
-        rsb             r2,  r2,  #0
-        vdup.32         q0,  r2
-1:      vld1.32         {q1},     [r0,:128]
-        vshl.s32        q1,  q1,  q0
-        vst1.32         {q1},     [r0,:128]!
-        subs            r1,  r1,  #4
-        bgt             1b
-        bx              lr
-endfunc
-
 function ff_float_to_fixed24_neon, export=1
 1:      vld1.32         {q0-q1},  [r1,:128]!
         vcvt.s32.f32    q0,  q0,  #24
@@ -109,29 +69,6 @@ function ff_ac3_extract_exponents_neon, export=1
         bx              lr
 endfunc
 
-function ff_apply_window_int16_neon, export=1
-        push            {r4,lr}
-        add             r4,  r1,  r3,  lsl #1
-        add             lr,  r0,  r3,  lsl #1
-        sub             r4,  r4,  #16
-        sub             lr,  lr,  #16
-        mov             r12, #-16
-1:
-        vld1.16         {q0},     [r1,:128]!
-        vld1.16         {q2},     [r2,:128]!
-        vld1.16         {q1},     [r4,:128], r12
-        vrev64.16       q3,  q2
-        vqrdmulh.s16    q0,  q0,  q2
-        vqrdmulh.s16    d2,  d2,  d7
-        vqrdmulh.s16    d3,  d3,  d6
-        vst1.16         {q0},     [r0,:128]!
-        vst1.16         {q1},     [lr,:128], r12
-        subs            r3,  r3,  #16
-        bgt             1b
-
-        pop             {r4,pc}
-endfunc
-
 function ff_ac3_sum_square_butterfly_int32_neon, export=1
         vmov.i64        q0,  #0
         vmov.i64        q1,  #0