arm: socfpga: misc: Exclude Agilex5 from clock manager base address retrieval

arm: socfpga: misc: Exclude Agilex5 from clock manager base address retrieval

Agilex5 retrieves its clock manager address via probing its own clock
driver model during SPL initialization.

Therefore, excluding Agilex5 from calling generic clock driver in misc
driver.

Signed-off-by: Alif Zakuan Yuslaimi <alif.zakuan.yuslaimi@altera.com>
Reviewed-by: Tien Fong Chee <tien.fong.chee@intel.com>