[PATCH 1/4 v2] msvcrt: Import _logb implementation from musl.

[Piotr Caban]

Signed-off-by: Piotr Caban 
---
  dlls/msvcrt/math.c    | 47 +++++++++++++++++++++++++------------------
  dlls/msvcrt/unixlib.c |  9 ---------
  dlls/msvcrt/unixlib.h |  1 -
  3 files changed, 27 insertions(+), 30 deletions(-)