kernel: atomics: support for 64-bit atomic operations

With this change, `atomic_t` is 32-bit for 32-bit architectures
and 64-bit for 64-bit architectures. More specifically,
`sizeof(atomic_t) == sizeof(long)`.

Fixes #39530

Signed-off-by: Christopher Friedt <chrisfriedt@gmail.com>

Author: cfriedt

include/sys/atomic.h

@@ -13,12 +13,13 @@
 #include <stddef.h>
 
 #include <zephyr/types.h>
+#include <sys/util_macro.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-typedef int atomic_t;
+typedef long atomic_t;
 typedef atomic_t atomic_val_t;
 typedef void *atomic_ptr_t;
 typedef atomic_ptr_t atomic_ptr_val_t;
@@ -76,7 +77,7 @@ typedef atomic_ptr_t atomic_ptr_val_t;
  */
 
 #define ATOMIC_BITS (sizeof(atomic_val_t) * 8)
-#define ATOMIC_MASK(bit) (1U << ((uint32_t)(bit) & (ATOMIC_BITS - 1U)))
+#define ATOMIC_MASK(bit) BIT((unsigned long)(bit) & (ATOMIC_BITS - 1U))
 #define ATOMIC_ELEM(addr, bit) ((addr) + ((bit) / ATOMIC_BITS))
 
 /**