Fix a few warnings

include/vlc_common.h

@@ -727,7 +727,7 @@ static inline void _SetQWBE( uint8_t *p, uint64_t i_qw )
     SetDWBE( p, ( i_qw >> 32)&0xffffffff );
 }
 
-#if WORDS_BIGENDIAN
+#ifdef WORDS_BIGENDIAN
 #   define hton16(i)   ( i )
 #   define hton32(i)   ( i )
 #   define hton64(i)   ( i )

include/vlc_config.h

@@ -45,9 +45,9 @@
 #define THREAD_COND_TIMEOUT             1
 
 /* The configuration file and directory */
-#ifdef SYS_BEOS
+#if defined (SYS_BEOS)
 #  define CONFIG_DIR                    "config/settings/VideoLAN Client"
-#elif __APPLE__
+#elif defined (__APPLE__)
 #  define CONFIG_DIR                    "Library/Preferences/VLC"
 #elif defined( WIN32 ) || defined( UNDER_CE )
 #  define CONFIG_DIR                    "vlc"