* cygcheck.cc (dump_sysinfo): Fix multiple Cygwin DLL test.
* path.cc: Fetch mount points from fstab files instead of from
registry. Use adapted functions copied from Cygwin DLL.
(mnt_t): Drop issys member. Define as "mnt_t" instead of "struct mnt_t"
subsequently.
(max_mount_entry): New variable.
(unconvert_slashes): Move to earlier location in file. Make inline.
(find2): Remove.
(get_cygdrive0): Remove.
(get_cygdrive): Remove.
(skip_ws): New function.
(find_ws): Ditto.
(conv_fstab_spaces): Ditto.
(read_flags): Ditto.
(from_fstab_line): Ditto.
(get_user): Ditto.
(from_fstab): Ditto.
(mnt_sort): Ditto.
(read_mounts): Drop old registry code. Fetch
"Software\Cygwin\Setup\rootdir" value from HKCU or HKLM key. Use
rootdir extracted from module path as fallback. Call from_fstab for
nouser and user mount points.
(setmntent): Check max_mount_entry to test if read_mounts must be
called.
(getmntent): Use MOUNT_SYSTEM flag instead of mnt_t's issys member.