Removed BOM

* The following compile error occurs.
* It was the cause of the BOM(UTF-8 byte order mark).

```bash
$ make
Making all in src
make[1]: Entering directory `/usr/local/src/s3fs-fuse/src'
if g++ -DPACKAGE_NAME=\"s3fs\" -DPACKAGE_TARNAME=\"s3fs\" -DPACKAGE_VERSION=\"1.77\" -DPACKAGE_STRING=\"s3fs\ 1.77\" -DPACKAGE_BUGREPORT=\"\" -DPACKAGE=\"s3fs\" -DVERSION=\"1.77\" -
DHAVE_MALLOC_TRIM=1  -I. -I.  -D_FILE_OFFSET_BITS=64 -I/usr/include/fuse -I/usr/include/libxml2 -I/usr/kerberos/include      -g -O2 -Wall -D_FILE_OFFSET_BITS=64 -MT s3fs.o -MD -MP -
MF ".deps/s3fs.Tpo" -c -o s3fs.o s3fs.cpp; \
        then mv -f ".deps/s3fs.Tpo" ".deps/s3fs.Po"; else rm -f ".deps/s3fs.Tpo"; exit 1; fi
In file included from s3fs.cpp:52:
s3fs_auth.h:1: error: stray '\357' in program
s3fs_auth.h:1: error: stray '\273' in program
s3fs_auth.h:1: error: stray '\277' in program
s3fs_auth.h:1: error: stray '#' in program
In file included from s3fs.cpp:52:
s3fs_auth.h:26:2: error: #endif without #if
s3fs_auth.h:1: error: 'ifndef' does not name a type
make[1]: *** [s3fs.o] Error 1
make[1]: Leaving directory `/usr/local/src/s3fs-fuse/src'
make: *** [all-recursive] Error 1
```