[rtems commit] sync.c: Revert previous patch with assertions

[Joel Sherril]

Module:    rtems
Branch:    master
Commit:    a37ffeb1369bc07248aaa9ef8b2b7b0b5064653a
Changeset: http://git.rtems.org/rtems/commit/?id=a37ffeb1369bc07248aaa9ef8b2b7b0b5064653a

Author:    Joel Sherrill <joel.sherrill at oarcorp.com>
Date:      Sat Dec  6 09:59:15 2014 -0600

sync.c: Revert previous patch with assertions

Some file systems do not support sync() at all and return an
error indicating this on any sync() call. In particular, the
IMFS is one of these and thus this assertion is tripped in
normal testing.

Since sync() is void per POSIX, the error just must be ignored.

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