staging: dwc2: do not clear pending interrupts twice

Pending interrupts clearing is done in dwc2_enable_common_interrupts
so we don't need to do it twice.

Signed-off-by: Julien Delacou <julien.delacou@st.com>
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>