[COMMITTED] math: Sync lgammaf with CORE-MATH

[Paul Zimmermann]

       Hi Adhemerval,

with the CORE-MATH test suite, I get:

zimmerma@thym:~/svn/core-math$ CORE_MATH_CHECK_STD=true CORE_MATH_LAUNCHER="/tmp/lib/ld-linux-x86-64.so.2 --library-path /tmp/lib:/usr/lib/x86_64-linux-gnu" LDFLAGS="-L /tmp/lib" ./check.sh lgammaf
Running exhaustive check in --rndn mode...
all ok
Running exhaustive check in --rndz mode...
Spurious overflow exception for x=0x1.895f1cp+121 (y=0x1.fffffep+127)

Please can you check?

Paul