selftests/bpf: Fix endianness issue in __qspinlock declaration

Copy the big-endian field declarations from qspinlock_types.h,
otherwise some properties won't hold on big-endian systems. For
example, assigning lock->val = 1 should result in lock->locked == 1,
which is not the case there.

Signed-off-by: Ilya Leoshkevich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: iii-i

tools/testing/selftests/bpf/progs/bpf_arena_spin_lock.h

@@ -32,6 +32,7 @@ extern unsigned long CONFIG_NR_CPUS __kconfig;
 struct __qspinlock {
 	union {
 		atomic_t val;
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 		struct {
 			u8 locked;
 			u8 pending;
@@ -40,6 +41,17 @@ struct __qspinlock {
 			u16 locked_pending;
 			u16 tail;
 		};
+#else
+		struct {
+			u16 tail;
+			u16 locked_pending;
+		};
+		struct {
+			u8 reserved[2];
+			u8 pending;
+			u8 locked;
+		};
+#endif
 	};
 };