MFV 316897

7586 remove #ifdef __lint hack from dmu.h

illumos/illumos-gate@4ba5b9616327ef64e8abc737d29b3faabc6ae68c
https://github.com/illumos/illumos-gate/commit/4ba5b9616327ef64e8abc737d29b3faabc6ae68c

https://www.illumos.org/issues/7586

The #ifdef __lint in dmu.h is ugly, and it would be nice not to duplicate it if
we add other inline functions into header files in ZFS, especially since it is
difficult to make any other solution work across all compilation targets. We
should switch to disabling the lint flags that are failing instead.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Dan Kimmel <dan.kimmel@delphix.com>