[ot] riscv: trace-events: remove unused ibex_gpio_combine_conflict trace

Signed-off-by: James Wainwright <james.wainwright@lowrisc.org>

Author: jwnrt

hw/riscv/trace-events

@@ -70,7 +70,3 @@ riscv_dtm_vm_state_change(const char *name, unsigned state) "VM state: %s[%u]"
 # ibex_common.c
 
 ibex_create_device(const char *pname, const char *name) "%s.%s"
-
-# ibex_gpio.c
-
-ibex_gpio_combine_conflict(const char *name, bool weak, bool elvel) "%s: w:%u %u"