remoteproc: Reset table_ptr in rproc_start() failure paths

Unwind the modified table_ptr and restore it to the local copy
upon any subsequent failures in the rproc_start() function. This
keeps the function to remain balanced on failures without the need
to balance any modified variables elsewhere.

While at this, do some minor cleanup of the extra lines between
the failure labels as well.

Signed-off-by: Suman Anna <s-anna@ti.com>
[bjorn: unconditionally set table_ptr to cached_table]
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>