ti: AM437x: Use generic EEPROM detection logic

Now that we have a generic TI eeprom logic which can be reused across
platforms, reuse the same.

This revision also includes fixes identified by Dave Gerlach
<d-gerlach@ti.com>

Cc: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Steven Kipisz <s-kipisz2@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>