MIPS: BMIPS: Remove maxcpus from BCM97435SVMB DTS

MIPS: BMIPS: Remove maxcpus from BCM97435SVMB DTS

Now that SMP properly works on 7435, do not restrict the number of core,
unleash them all.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: john@phrozen.org
Cc: cernekee@gmail.com
Cc: jon.fraser@broadcom.com
Cc: jaedon.shin@gmail.com
Cc: dragan.stancevic@gmail.com
Cc: jogo@openwrt.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12379/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>