allow setting exception handler to the same value, as this might happen if exceptions are set dynamically on both cores, but VTOR is the same... this should indeed cause an error if the values differ, but not otherwise (#385)

src/rp2_common/hardware_exception/exception.c

@@ -46,7 +46,7 @@ exception_handler_t exception_set_exclusive_handler(enum exception_number num, e
 #if !PICO_NO_RAM_VECTOR_TABLE
     uint32_t save = save_and_disable_interrupts();
     exception_handler_t current = exception_get_vtable_handler(num);
-    hard_assert(exception_is_compile_time_default(current));
+    hard_assert(handler == current || exception_is_compile_time_default(current));
     set_raw_exception_handler_and_restore_interrupts(num, handler, save);
 #else
     panic_unsupported();