EDAC/amd64: Remove NUM_CONTROLLERS macro

EDAC/amd64: Remove NUM_CONTROLLERS macro

Currently, the NUM_CONTROLLERS macro is used to limit the amount of memory
controllers (UMCs) available per node. The number of UMCs available per node,
however, is already cached by the max_mcs variable of struct amd64_pvt.

Allocate the relevant data structures dynamically using the variable instead
of static allocation through the macro.

The max_mcs variable is used for legacy systems too. These systems have a max
of 2 controllers. Since the default value of max_mcs, set in per_family_init(),
is 2, these legacy systems are also covered.

Signed-off-by: Avadhut Naik <avadhut.naik@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20251106015727.1987246-1-avadhut.naik@amd.com