Adjust function definition in subr_autoconf.c to avoid clang 15 warnings

With clang 15, the following -Werror warning is produced:

sys/kern/subr_autoconf.c:119:34: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
run_interrupt_driven_config_hooks()
                                 ^
                                  void

This is because run_interrupt_driven_config_hooks() is declared with a
(void) argument list, but defined with an empty argument list. Make the
definition match the declaration.

MFC after: 3 days

(cherry picked from commit 3c8f0790dd038ce646f140b7aad23b4e698c0522)