msm: socinfo: fix memory leak in socinfo_init_sysdev

Under certain error paths in socinfo_init_sysdev the soc_dev_attr
struct does not get freed. Fix this memory leak.

Change-Id: I22a4b60722367798dc5171fe7c00fc7c814168cb
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>