clk: x86: Rename clk-lpt to more specific clk-lpss-atom

The LPT stands for Lynxpoint PCH. However the driver is used on a few
Intel Atom SoCs. Rename it to reflect this in a way how another clock
driver, i.e. clk-pmc-atom, is called.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210722193450.35321-1-andriy.shevchenko@linux.intel.com
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>