ARM: at91/dt: sam9263: fix PLLB frequencies

PLLB input and output ranges were wrongly copied from at91sam9261 as the
datasheet didn't mention explicitly PLLB. Correct their values.

This fixes USB.

Reported-by: Andreas Henriksson <andreas.henriksson@endian.se>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Andreas Henriksson <andreas.henriksson@endian.se>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>