set SDLMIXER_VENDORED to ON and vendor the required libraries into libs/SDL3_mixer/external

disable SDLMIXER_VORBIS_VORBISFILE
add ogg v1.3.5-SDL
add opus v1.4.x-SDL
add opusfile v0.13-git-SDL

libs/SDL3_mixer/external/opus/celt_sources.mk

@@ -0,0 +1,52 @@
+CELT_SOURCES = \
+celt/bands.c \
+celt/celt.c \
+celt/celt_encoder.c \
+celt/celt_decoder.c \
+celt/cwrs.c \
+celt/entcode.c \
+celt/entdec.c \
+celt/entenc.c \
+celt/kiss_fft.c \
+celt/laplace.c \
+celt/mathops.c \
+celt/mdct.c \
+celt/modes.c \
+celt/pitch.c \
+celt/celt_lpc.c \
+celt/quant_bands.c \
+celt/rate.c \
+celt/vq.c
+
+CELT_SOURCES_X86_RTCD = \
+celt/x86/x86cpu.c \
+celt/x86/x86_celt_map.c
+
+CELT_SOURCES_SSE = \
+celt/x86/pitch_sse.c
+
+CELT_SOURCES_SSE2 = \
+celt/x86/pitch_sse2.c \
+celt/x86/vq_sse2.c
+
+CELT_SOURCES_SSE4_1 = \
+celt/x86/celt_lpc_sse4_1.c \
+celt/x86/pitch_sse4_1.c
+
+CELT_SOURCES_ARM_RTCD = \
+celt/arm/armcpu.c \
+celt/arm/arm_celt_map.c
+
+CELT_SOURCES_ARM_ASM = \
+celt/arm/celt_pitch_xcorr_arm.s
+
+CELT_AM_SOURCES_ARM_ASM = \
+celt/arm/armopts.s.in
+
+CELT_SOURCES_ARM_NEON_INTR = \
+celt/arm/celt_neon_intr.c \
+celt/arm/pitch_neon_intr.c
+
+CELT_SOURCES_ARM_NE10 = \
+celt/arm/celt_fft_ne10.c \
+celt/arm/celt_mdct_ne10.c