toolchain: Introduce __ALIGNED(x) macro

The __ALIGNED(x) macro may be used to tell the compiler to align the
symbol's address to an 'x' byte boundary.  Note that 'x' must be a
power of two.

Signed-off-by: Peter Mitsis <peter.mitsis@gmail.com>

Author: PeterMitsis

code/globalincs/toolchain/clang.h

@@ -21,6 +21,7 @@
 #define SCP_FORMAT_STRING_ARGS(x,y)  __attribute__((format(printf, x, y)))
 
 #define __UNUSED __attribute__((__unused__))
+#define __ALIGNED(x)  __attribute__((__aligned__(x)))
 
 #ifdef NO_RESTRICT_USE
 #	define RESTRICT

code/globalincs/toolchain/gcc.h

@@ -21,6 +21,7 @@
 #define SCP_FORMAT_STRING_ARGS(x,y)  __attribute__((format(printf, x, y)))
 
 #define __UNUSED __attribute__((__unused__))
+#define __ALIGNED(x)  __attribute__((__aligned__(x)))
 
 #ifdef NO_RESTRICT_USE
 #   define RESTRICT

code/globalincs/toolchain/mingw.h

@@ -21,6 +21,7 @@
 #define SCP_FORMAT_STRING_ARGS(x,y)  __attribute__((format(printf, x, y)))
 
 #define __UNUSED __attribute__((__unused__))
+#define __ALIGNED(x)  __attribute__((__aligned__(x)))
 
 #ifdef NO_RESTRICT_USE
 #   define RESTRICT

code/globalincs/toolchain/msvc.h

@@ -24,6 +24,7 @@
 
 #define __attribute__(x)
 #define __UNUSED
+#define __ALIGNED(x)  __declspec(align(x))
 
 #ifdef NO_RESTRICT_USE
 #   define RESTRICT