remove math code for newlib

libm is a frequently used lib. Newlib is compiled with
-ffunction-sections in recent GCC tool chains. The linker would just
link in the functions that have been referenced. So setting this won't
result in bigger text size.

Usb device:correct the macro

Usb-device

Newlib already have optimized and full featured math implementation. To
use it, one should add:

    env['LIBS'] = ['m']

or equivalent to the SConstruct.

fix math.h

Declare sin/cos and M_PI in math.h.

remove product ID

add a dcd operation to send status in control transfer

Correct crlf

LGTM, thanks!

1) elm fatfs can do mkfs without mounting first, 2) use new mkfs 3)change linebreak in dfs_uffs.c to unix

elm fatfs support mkfs with no need to  run dfs_mount elm first; and can mount/umount/mkfs without reset any more

Ignore temporary files and force unix format in repository as in ART