memory: bt1-l2-ctl: Remove not-going-to-be-supported code for Baikal SoC

memory: bt1-l2-ctl: Remove not-going-to-be-supported code for Baikal SoC

As noticed in the discussion [1] the Baikal SoC and platforms
are not going to be finalized, hence remove stale code.

Link: https://lore.kernel.org/lkml/22b92ddf-6321-41b5-8073-f9c7064d3432@infradead.org/
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260225173930.3819351-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>