ARM: zynq: Fix pmu register description coding style

Drop the space before/after '<' and '>'; and
separate the entries to be a bit more readable.

Reported-by: Julia Cartwright <julia@ni.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Series-to: arm-soc
Series-cc: julia@ni.com