soc: xtensa: esp32: fix app cpu boot

procedure by setting its PC to 0 before reset.

Signed-off-by: Felipe Neves <felipe.neves@linaro.org>
diff --git a/soc/xtensa/esp32/esp32-mp.c b/soc/xtensa/esp32/esp32-mp.c
index fd3b2f1..3ab9bdd 100644
--- a/soc/xtensa/esp32/esp32-mp.c
+++ b/soc/xtensa/esp32/esp32-mp.c
@@ -183,6 +183,8 @@
 	esp_rom_Cache_Flush(1);
 	esp_rom_Cache_Read_Enable(1);
 
+	esp_rom_ets_set_appcpu_boot_addr((void *)0);
+
 	RTC_CNTL_SW_CPU_STALL &= ~RTC_CNTL_SW_STALL_APPCPU_C1;
 	RTC_CNTL_OPTIONS0     &= ~RTC_CNTL_SW_STALL_APPCPU_C0;
 	DPORT_APPCPU_CTRL_B   |= DPORT_APPCPU_CLKGATE_EN;