crypto: caam - make write transactions bufferable on PPC platforms

crypto: caam - make write transactions bufferable on PPC platforms

commit e7a7104e432c0db8469ca3568daf4f1d1afe3e73 upstream.

Previous change (see "Fixes" tag) to the MCFGR register
clears AWCACHE[0] ("bufferable" AXI3 attribute) (which is "1" at POR).

This makes all writes non-bufferable, causing a ~ 5% performance drop
for PPC-based platforms.

Rework previous change such that MCFGR[AWCACHE]=4'b0011
(bufferable + cacheable) for all platforms.
Note: For ARM-based platforms, AWCACHE[0] is ignored
by the interconnect IP.

Fixes: f10967495144 ("crypto: caam - fix snooping for write transactions")
Signed-off-by: Horia Geant? <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>