arch/powerpc: drop GENERIC_PTDUMP from mpc885_ads_defconfig

arch/powerpc: drop GENERIC_PTDUMP from mpc885_ads_defconfig

GENERIC_PTDUMP gets selected on powerpc explicitly and hence can be
dropped off from mpc885_ads_defconfig.  Replace with CONFIG_PTDUMP_DEBUGFS
instead.

Link: https://lkml.kernel.org/r/20250226122404.1927473-3-anshuman.khandual@arm.com
Fixes: e084728393a5 ("powerpc/ptdump: Convert powerpc to GENERIC_PTDUMP")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>