[Qemu-devel] softfloat: fix NaN propagation for MIPS and PowerPC + cleanup

[Aurelien Jarno]

This patch series start by a cleanup to remove dead HPPA code, and then
implement correct NaN propagation rules for MIPS and PowerPC, following
commit 354f211b1a49a7387929e22d6e63849fcba48f8a.