package/kvazaar: disable on PowerPC, PowerPC64 and PowerPC64le

package/kvazaar: disable on PowerPC, PowerPC64 and PowerPC64le

kvazaar is affected by three different build issues on PowerPC and
related architectures:

 - On PowerPC64, the build fails due to the use of a deprecated
   vec_lvsl() function:

strategies/altivec/picture-altivec.c: In function ‘reg_sad_altivec’:
strategies/altivec/picture-altivec.c:43:5: error: vec_lvsl is deprecated for little endian; use assignment for unaligned loads and stores [-Werror=deprecated]
perm1 = vec_lvsl(0, &data1[y * stride1]);
^~~~~

   This bug has been reported upstream at:
   https://github.com/ultravideo/kvazaar/issues/172

 - On PowerPC 8548, the build fails due to mixing AltiVec and E500
   instructions:

strategies/altivec/picture-altivec.c:1:0: error: AltiVec and E500 instructions cannot coexist

   This bug has been reported upstream at:
   https://github.com/ultravideo/kvazaar/issues/173

 - On PowerPC e500mc, because Altivec is not supported on this target:

strategies/altivec/picture-altivec.c:1:0: error: AltiVec not supported in this target

   This bug has been reported upstream at:
   https://github.com/ultravideo/kvazaar/issues/174

Fixes:

  http://autobuild.buildroot.net/results/486/486757f04bc73736b64d18c3298216280be897b1
  http://autobuild.buildroot.net/results/45d/45d22c9f2f5b593bed286319105c82cbc3396835
  http://autobuild.buildroot.net/results/76c/76c76191f84748326d76fe0cc89456a72738a06b

Signed-off-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>