- Update to release GMP 5.0.5
* A bug causing AMD 11h processors to be treated like AMD 10h has been fixed.
* A bug affecting recent Intel Sandy Bridge CPUs resulting in
configuration failures has been fixed.

- Remove redundant --host specification on %configure.

- Update to release GMP 5.0.4
* Thresholds in mpn_powm_sec for both fat and non-fat builds are now used
safely, plugging a one-word buffer overrun introduced in the 5.0.3 release
(for non-fat) and a multi-word buffer overrun that existed since 5.0 (for
fat). (We have not been able to provoke malign stack smashing in any of
the ~100 configurations explored by the GMP nightly builds, but the bug
should be assumed to be exploitable.)
* Two bugs in multiplication code causing incorrect computation with
extremely low probability have been fixed.
* A bug in the test suite causing buffer overruns during "make check",
sometimes leading to subsequent malloc crashes, has been fixed.
* Two bugs in the gcd code have been fixed. They could lead to incorrect
results, but for uniformly distributed random operands, the likelihood for
that is infinitesimally small. (There was also a third bug, but that was
an incorrect ASSERT, which furthermore was not enabled by default.)
* A bug affecting 32-bit PowerPC division has been fixed. The bug caused
miscomputation for certain divisors in the range 2^32 ... 2^64-1 (about 1
in 2^30 of these).

- Remove redundant tags/sections (see specfile guidelines)