Bluetooth: MGMT: Fix backward compatibility with userspace

Bluetooth: MGMT: Fix backward compatibility with userspace

bluetoothd has a bug with makes it send extra bytes as part of
MGMT_OP_ADD_EXT_ADV_DATA which are now being checked to be the
exact the expected length, relax this so only when the expected
length is greater than the data length to cause an error since
that would result in accessing invalid memory, otherwise just
ignore the extra bytes.

Link: https://lore.kernel.org/linux-bluetooth/20260602204749.210857-1-luiz.dentz@gmail.com/T/#u
Fixes: d3f7d17960ed ("Bluetooth: MGMT: validate Add Extended Advertising Data length")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>