Merge bitcoin#11140: Trivial: Improve #endif comments

ac1cf8d Trivial: Improve #endif comments (danra)

Pull request description:

  Improve the #endif comments for the '#if HAVE_DECL_BSWAP_XX == 0' preprocessor conditions, so each shows the full condition which it closes.

Tree-SHA512: f533311fa48cb2f46f6490b6c965ad5f8861dcfad70c56d70e31fa989b422880c78b2dd6f24f648b19d3a22f767606e0de5cf1cb71445012b42c97ac2149295e

src/compat/byteswap.h

@@ -37,15 +37,15 @@ inline uint16_t bswap_16(uint16_t x)
 {
     return (x >> 8) | (x << 8);
 }
-#endif // HAVE_DECL_BSWAP16
+#endif // HAVE_DECL_BSWAP16 == 0
 
 #if HAVE_DECL_BSWAP_32 == 0
 inline uint32_t bswap_32(uint32_t x)
 {
     return (((x & 0xff000000U) >> 24) | ((x & 0x00ff0000U) >>  8) |
             ((x & 0x0000ff00U) <<  8) | ((x & 0x000000ffU) << 24));
 }
-#endif // HAVE_DECL_BSWAP32
+#endif // HAVE_DECL_BSWAP32 == 0
 
 #if HAVE_DECL_BSWAP_64 == 0
 inline uint64_t bswap_64(uint64_t x)
@@ -59,7 +59,7 @@ inline uint64_t bswap_64(uint64_t x)
           | ((x & 0x000000000000ff00ull) << 40)
           | ((x & 0x00000000000000ffull) << 56));
 }
-#endif // HAVE_DECL_BSWAP64
+#endif // HAVE_DECL_BSWAP64 == 0
 
 #endif // defined(__APPLE__)