kernel: typedef k_mem_domain_t and _mem_domain_info_t

Create alias for struct k_mem_domain into k_mem_domain_t,
and struct _mem_domain_info into _mem_domain_info_t via
typedef. These are needed to generate offsets via
GEN_OFFSET_SYM.

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

Author: dcpleung

include/zephyr/app_memory/mem_domain.h

@@ -89,6 +89,8 @@ struct k_mem_domain {
 	uint8_t num_partitions;
 };
 
+typedef struct k_mem_domain k_mem_domain_t;
+
 /**
  * Default memory domain
  *

include/zephyr/kernel/thread.h

@@ -196,6 +196,7 @@ struct _mem_domain_info {
 	struct k_mem_domain *mem_domain;
 };
 
+typedef struct _mem_domain_info _mem_domain_info_t;
 #endif /* CONFIG_USERSPACE */
 
 #ifdef CONFIG_THREAD_USERSPACE_LOCAL_DATA