fs: ecryptfs: readdir: constify actor
actor is a constant in dir_context struct and
because of that we run into following build failure:
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fs/ecryptfs/file.c: In function ‘ecryptfs_readdir’:
fs/ecryptfs/file.c:130:2: error: assignment of read-only member ‘actor’
make[2]: *** [fs/ecryptfs/file.o] Error 1
make[1]: *** [fs/ecryptfs] Error 2
make: *** [fs] Error 2
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This fix is based on commit:
b2497fc3057a([readdir] constify ->actor)
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>