[kernel] Add hook for malloc services

Including the patch for memory allocation, testsuites and fixups of
static analysis.

Signed-off-by: Shell <smokewood@qq.com>

components/lwp/lwp.h

@@ -208,6 +208,8 @@ void lwp_uthread_ctx_restore(void);
 
 int lwp_setaffinity(pid_t pid, int cpu);
 
+pid_t exec(char *filename, int debug, int argc, char **argv);
+
 /* ctime lwp API */
 int timer_list_free(rt_list_t *timer_list);
 

components/lwp/lwp_user_mm.c

@@ -148,7 +148,9 @@ void lwp_aspace_switch(struct rt_thread *thread)
         aspace = lwp->aspace;
     }
     else
+    {
         aspace = &rt_kernel_space;
+    }
 
     from_tbl = rt_hw_mmu_tbl_get();
     if (aspace->page_table != from_tbl)