Kernel: Define PT_READ_I and PT_READ_D

Looking at how these two constants are commonly used in other systems,
we should be able to mimic their behavior using our PT_PEEK constant.

For example, see:
https://man.netbsd.org/NetBSD-6.0.1/i386/ptrace.2

Kernel/API/POSIX/sys/ptrace.h

@@ -24,6 +24,9 @@ extern "C" {
 #define PT_POKEDEBUG 10
 #define PT_PEEKDEBUG 11
 
+#define PT_READ_I PT_PEEK
+#define PT_READ_D PT_PEEK
+
 #define DEBUG_STATUS_REGISTER 6
 #define DEBUG_CONTROL_REGISTER 7