Since commit 8fa6abb6f4 ("Expose clang's alignment builtins and use
them for roundup2/rounddown2"), clang emits warnings for several
alignment operations in these drivers because the operation is a no-op.
The compiler is arguably being too strict here, but in the meantime
let's silence the warnings by conditionally compiling the alignment
operations.
Reviewed by: arichardson, hselasky
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D28576
compilation under FreeBSD. The mthca driver was temporarily removed as
part of the Linux 4.9 RoCE/infinband upgrade.
Top commit in Linux source tree:
69973b830859bc6529a7a0468ba0d80ee5117826
Sponsored by: Mellanox Technologies
