ir/value: Replace includes with forward declarations

enum classes are still considered complete types when forward declared
(as the compiler knows the exact size of the type from the declaration
alone). The only difference in this case being that the members of the
enum class aren't visible. Given we don't use the members within this
header in any way, we can simply forward declare them here and remove
the inclusions.

src/frontend/ir/value.h

@@ -10,14 +10,22 @@
 
 #include "common/assert.h"
 #include "common/common_types.h"
-#include "frontend/A32/types.h"
-#include "frontend/A64/types.h"
-#include "frontend/ir/cond.h"
 #include "frontend/ir/type.h"
 
+namespace Dynarmic::A32 {
+enum class ExtReg;
+enum class Reg;
+}
+
+namespace Dynarmic::A64 {
+enum class Reg;
+enum class Vec;
+}
+
 namespace Dynarmic::IR {
 
 class Inst;
+enum class Cond;
 
 /**
  * A representation of a value in the IR.

src/ir_opt/a32_get_set_elimination_pass.cpp

@@ -8,6 +8,7 @@
 
 #include "common/assert.h"
 #include "common/common_types.h"
+#include "frontend/A32/types.h"
 #include "frontend/ir/basic_block.h"
 #include "frontend/ir/opcodes.h"
 #include "frontend/ir/value.h"

src/ir_opt/a64_get_set_elimination_pass.cpp

@@ -8,6 +8,7 @@
 
 #include "common/assert.h"
 #include "common/common_types.h"
+#include "frontend/A64/types.h"
 #include "frontend/ir/basic_block.h"
 #include "frontend/ir/ir_emitter.h"
 #include "frontend/ir/opcodes.h"

tests/A32/fuzz_arm.cpp

@@ -25,6 +25,7 @@
 #include "frontend/A32/location_descriptor.h"
 #include "frontend/A32/PSR.h"
 #include "frontend/A32/translate/translate.h"
+#include "frontend/A32/types.h"
 #include "frontend/ir/basic_block.h"
 #include "frontend/ir/location_descriptor.h"
 #include "ir_opt/passes.h"

tests/A64/fuzz_with_unicorn.cpp

@@ -19,6 +19,7 @@
 #include "frontend/A64/decoder/a64.h"
 #include "frontend/A64/location_descriptor.h"
 #include "frontend/A64/translate/translate.h"
+#include "frontend/A64/types.h"
 #include "frontend/ir/basic_block.h"
 #include "frontend/ir/opcodes.h"
 #include "fuzz_util.h"