clk: T-Head: Disable on 32-bit Targets

clk: T-Head: Disable on 32-bit Targets

This fails to build on 32-bit targets because of a missing __udivdi3.
IIRC the right way to fix that is to avoid the division, but I just want
a tree that builds and the only real T-Head platforms are 64-bit right
now.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20240719151027.16152-1-palmer@rivosinc.com
Acked-by: Drew Fustini <drew@pdp7.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>