Commit 523d6e9f (arm64:mm: free the useless initial page table)
introduced a BUG_ON checking for the allocation type but it was
referring the early_alloc() function in the __init section. This patch
changes the check to slab_is_available() and also relaxes the BUG to a
WARN_ON_ONCE.
Reported-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>