riscv: Use SYM_*() assembly macros instead of deprecated ones

ENTRY()/END()/WEAK() macros are deprecated and we should make use of the
new SYM_*() macros [1] for better annotation of symbols. Replace the
deprecated ones with the new ones and fix wrong usage of END()/ENDPROC()
to correctly describe the symbols.

[1] https://docs.kernel.org/core-api/asm-annotations.html

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231024132655.730417-3-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

riscv: add riscv rethook implementation

Implement the kretprobes on riscv arch by using rethook machenism
which abstracts general kretprobe info into a struct rethook_node
to be embedded in the struct kretprobe_instance.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Binglei Wang <l3b2w1@gmail.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221025151831.1097417-1-conor@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>