With clang 15, the following -Werror warning is produced:
sys/riscv/riscv/db_trace.c:56:23: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
db_md_list_watchpoints()
^
void
This is because db_md_list_watchpoints() is declared with a (void)
argument list, but defined with an empty argument list. Make the
definition match the declaration.
MFC after: 3 days