Bluetooth: hidp: Fix handling of strncpy for hid->name information

This fixes two issues with setting hid->name information.

  CC      net/bluetooth/hidp/core.o
In function ‘hidp_setup_hid’,
    inlined from ‘hidp_session_dev_init’ at net/bluetooth/hidp/core.c:815:9,
    inlined from ‘hidp_session_new’ at net/bluetooth/hidp/core.c:953:8,
    inlined from ‘hidp_connection_add’ at net/bluetooth/hidp/core.c:1366:8:
net/bluetooth/hidp/core.c:778:2: warning: ‘strncpy’ output may be truncated copying 127 bytes from a string of length 127 [-Wstringop-truncation]
  strncpy(hid->name, req->name, sizeof(req->name) - 1);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

  CC      net/bluetooth/hidp/core.o
net/bluetooth/hidp/core.c: In function ‘hidp_setup_hid’:
net/bluetooth/hidp/core.c:778:38: warning: argument to ‘sizeof’ in ‘strncpy’ call is the same expression as the source; did you mean to use the size of the destination? [-Wsizeof-pointer-memaccess]
  strncpy(hid->name, req->name, sizeof(req->name));
                                      ^

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>