PowerPC: initial support for LE build

This patch adds initial support for PowerPC ELFv2 Little Endian
build.
libdfp: Fix endian macro check

This patch fixes some endian macros check by replacing BYTE_ORDER for
__BYTE_ORDER and BIG_ENDIAN by __BIG_ENDIAN.
libdfp: Fixes for isinfd

This patch has three changes:
1. isinfd[32|64|128] now return -1 for minux infinity
2. powerpc isinf128d now uses the isinf32.d template instead of the
   is_template.h
3. powerpc isinf32d  was simplified to check the cr0 value in C
   instead of assembly tests.
libdfp: Fixes for isfinited

This patches makes PowerPC HW DFP code return a positive integer as
other implementations. It also simplifies the is_template.h implementation
by chekcing cr0 result in C instead of assembly.
libdfp: Fix issues with getexp when exp is DECIMAL_BIAS
libdfp: Remove compiler warnings by unused variables
libdfp: Fix test-bfp-conversions segfault due recursive calls

This patch fixes some builtins used on the conversion functions and also
the recursive calls in the long double calls where long doulbe operations
are being used resulting in recursive calls generated by the compiler.
libdfp: Add support to POWER8

This patch add support to build with --with-cpu=power8. POWER8 builds
uses the Implies for POWER7.
PowerPC: fix endian issue when reading rounding mode

This patch fixes the test-round with PowerPC hardware instruction
in LE mode. It make the read endian neutral.
PowerPC: fix the numdigits for LE

This patch fixes the numdigits PowerPC implementation by setting the
decimal bias mask in a endianess neutral way. The patch fixes the
test-numdigits along with related testcases (test-printf, test-istream,
test-ostream, and test-ostream-g-spec) for LE.
libdfp: Fix compile warnings in tests
libdfp: Optimize the host to/from ieee functions

This patch changes the way the host to/from ieee copies data by using
word and doubleword loads and store and by also using compiler builtins
for byte swap.
libdfp: Add more coverage for logd tests

This patch adds more coverage for logd test with tests for logd32 and
logd128. It also fixes the file indentation.
libdfp: Fix LE issues with decimal to decNumber

This patch fixes the decimal[32|64|128]FromNumber and decimal[32|64|128]ToNumber
functions for little-endian.
PowerPC: Fix endianess issue with setexp

This patch fixes an endianess issue with setexp when setting the
exponent.
PowerPC: Fix left_justify for Little Endian

This patch cleanups the 'left_justify' powerpc implementation by fixing
it for LE and removing the VSX optimizations (to avoid code complexity).
It also removed some compile warnings with multiple file inclusion
due DECIMAL_BIAS/DECIMAL_BIAS_DOUBLE redefine.
libdfp: Update version for 1.0.9 release.
libdfp: Add generic macros and functions

This patch adds a header with generic macros and functions to transform
the _Decimal type to and from integer types.
libdfp: New <math.h> macro named issignaling to check for a signaling NaN (sNaN).

It is based on draft TS 18661 and this patch adds implementation for
both software based and PowerPC hardware dfp.
Merge branch 'master-le-port'