sparc32: mm: Don't try to free page-table pages if ctor() fails

The pages backing page-table allocations for SRMMU are allocated via
memblock as part of the "nocache" region initialisation during
srmmu_paging_init() and should not be freed even if a later call to
pgtable_pte_page_ctor() fails.

Remove the broken call to __free_page().

Cc: David S. Miller <davem@davemloft.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Fixes: 1ae9ae5f ("sparc: handle pgtable_page_ctor() fail")
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>