devel/libexplain: Unbreak after base r357412

libexplain/buffer/open_flags.c:187:10: error: duplicate case value '262144'

case O_EXEC:
     ^

/usr/include/fcntl.h:121:17: note: expanded from macro 'O_EXEC'
#define O_EXEC 0x00040000 /* Open for execute only */

^

libexplain/buffer/open_flags.c:180:11: note: previous case defined here

case O_SEARCH:
     ^

/usr/include/fcntl.h:122:18: note: expanded from macro 'O_SEARCH'
#define O_SEARCH O_EXEC

^

/usr/include/fcntl.h:121:17: note: expanded from macro 'O_EXEC'
#define O_EXEC 0x00040000 /* Open for execute only */

^

1 error generated.

http://beefy17.nyi.freebsd.org/data/head-i386-default/p525358_s357606/logs/libexplain-1.3.D012_6.log