USB host: Adding USB ehci & ohci support for spear platform

This patch adds support for ehci and ohci controller in the SPEAr platform.

Changes since V2:
added clear_tt_buffer_complete in ehci_spear_hc_driver

Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>