lib: rsa: cosmetic: fix building warning

add initialization of variable 'node',this can aviod the building
warning:

    'node' may be used uninitialized [-Wmaybe-uninitialized]

Signed-off-by: Haijun Qin <qinhaijun@eswincomputing.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed