change: move def. of pid_t to gblibc

include/kernel/process.hpp

@@ -8,6 +8,7 @@
 #include <kernel/task.h>
 #include <kernel/vfs.hpp>
 #include <stdint.h>
+#include <sys/types.h>
 #include <types/allocator.hpp>
 #include <types/cplusplus.hpp>
 #include <types/hash_map.hpp>
@@ -18,8 +19,6 @@
 #include <types/string.hpp>
 #include <types/types.h>
 
-typedef size_t pid_t;
-
 class process;
 struct thread;