ffmpeg: Enable zbb manip extensions for rv32/rv64

This is required with clang after the assembly file is added which uses
these instructions. it works with gcc because it uses
.option directive to enable zbb extentions in toolchain on the fly
clang does not have similar option

| <instantiation>:6:21: warning: unknown option, expected 'push', 'pop', 'rvc', 'norvc', 'relax' or 'norelax'
|             .option arch, +zbb

This fixes

| src/libavcodec/riscv/bswapdsp_rvb.S:61:9: error: instruction requires the following: 'Zbb' (Basic Bit-Manipulation) or 'Zbkb' (Bitmanip instructions for Cryptography)
|         rev8 t0, t0
|         ^

Signed-off-by: Khem Raj <raj.khem@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/conf/nonclangable.conf b/conf/nonclangable.conf
index 2c83f1a..6597bce 100644
--- a/conf/nonclangable.conf
+++ b/conf/nonclangable.conf
@@ -254,6 +254,9 @@ CFLAGS:append:pn-seatd:toolchain-clang = " -Wno-sign-compare"
 CXXFLAGS:remove:pn-mozjs:toolchain-clang = "-fno-tree-vrp"
 CFLAGS:remove:pn-mozjs:toolchain-clang = "-fno-tree-vrp"
 
+CFLAGS:append:pn-ffmpeg:riscv64 = " -march=rv64gczbb"
+CFLAGS:append:pn-ffmpeg:riscv32 = " -march=rv32gczbb"
+
 TUNE_CCARGS:remove:pn-omxplayer:toolchain-clang = "-no-integrated-as"
 TUNE_CCARGS:remove:pn-nfs-utils:toolchain-clang = "-Qunused-arguments"