add a basic structure for disassembler + executor

Instructions added
Branch and Exchange (BX)
Branch and Link (B)
Multiply and Accumulate (MUL, MLA)
Multiply Long and Accumulate (SMULL, SMLAL, UMULL, UMLAL)
Single data swap (SWP)
[WIP] Halfword Transfer (STRH, LDRH)

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

src/cpu/psr.hh

@@ -1,6 +1,5 @@
 #pragma once
 
-#include "util/bits.hh"
 #include "utility.hh"
 #include <cstdint>
 
@@ -14,7 +13,7 @@ class Psr {
     void set_mode(Mode mode);
 
     // State : [5]
-    bool state() const;
+    State state() const;
     void set_state(State state);
 
 #define GET_SET_NTH_BIT_FUNCTIONS(name)                                        \
@@ -43,6 +42,8 @@ class Psr {
 
 #undef GET_SET_NTH_BIT_FUNCTIONS
 
+    bool condition(Condition cond) const;
+
   private:
     static constexpr uint32_t PSR_CLEAR_RESERVED = 0xf00000ff;
     static constexpr uint32_t PSR_CLEAR_MODE     = 0x0b00000;