davinci: edma: fix coding style issue related to usage of braces

In the edma driver, there are couple of instances where braces
are used for a single statement 'if' construct.

There are other instances where 'else' part of the if-else construct
does not use braces even if the 'if' part is a multi-line statement.

This patch fixes both.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>