The generic SRAM binding currently only allows for child nodes of an SRAM
to be called sram too. However, these are also called sections in a number
of device tree, which seems a bit more accurate.

Let's change the name pattern to allow both.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Rob Herring <robh@kernel.org>