arm64: fpsimd: Use assembler for SVE instructions

arm64: fpsimd: Use assembler for SVE instructions

Historically we supported assemblers which could not assemble SVE
instructions. We dropped support for such assemblers in commit:

  118c40b7b503 ("kbuild: require gcc-8 and binutils-2.30")

Since that commit, all supported assemblers (binutils and LLVM) are
capable of assembling SVE instructions, and there's no need for us to
manually encode SVE instructions.

Rely on the assembler to encode SVE instructions, and remove the manual
encoding. The various _sve_<insn> macros are kept for now, and will be
cleaned up in subsequent patches.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oupton@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>