serial: sh-sci: Support generic SCLSR overrun detection.
serial: sh-sci: Support generic SCLSR overrun detection.

For all ports with a valid SCLSR register we can use the generic FIFO
overrun detection logic. Test the validity of the SCLSR register rather
than depending explicitly on port type, which can be ambiguous for the
SCIFA/B types.

Signed-off-by: Paul Mundt <38b52dbb5f0b63d149982b6c5de788ec93a89032@linux-sh.org>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas