arch: xtensa: include soc.h to fix build errors

There are places where soc.h must be included. So include it.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>

arch/xtensa/core/irq_offload.c

@@ -8,6 +8,11 @@
 #include <arch/xtensa/arch.h>
 #include <xtensa_api.h>
 
+#ifndef CONFIG_BOARD_QEMU_XTENSA
+/* qemu_xtensa has no soc definitions */
+#include <soc.h>
+#endif
+
 /*
  * Xtensa core should support software interrupt in order to allow using
  * irq_offload feature

include/arch/xtensa/xtensa_irq.h

@@ -13,6 +13,9 @@
 
 #ifdef CONFIG_MULTI_LEVEL_INTERRUPTS
 
+/* for _soc_irq_*() */
+#include <soc.h>
+
 #define CONFIG_NUM_IRQS (XCHAL_NUM_INTERRUPTS +\
 			(CONFIG_NUM_2ND_LEVEL_AGGREGATORS +\
 			CONFIG_NUM_3RD_LEVEL_AGGREGATORS) *\