memory: tegra234: drop dead NULL check in tegra234_mc_icc_aggregate()

In tegra234_mc_icc_aggregate(), the 'if (mc)' check inside the
CPU-cluster branch is always true.  'mc' was already dereferenced
via 'mc->bwmgr_mrq_supported' a few lines above, so if it were NULL
the function would have faulted there.  Drop the redundant check.

Reported-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://patch.msgid.link/20260527140127.49172-4-sumitg@nvidia.com
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>