usb: dwc2: increase timeout in wait_for_chhltd

This patch increases timeout to 2s.
It was seen on 2 USB devices (Verbatim STORE N GO 070B4AED0FB22358 and
USB DISK 2.0 9000729BA41DDF40) that the request sense command takes
between 1.3s and and 1.5s.

Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>