evas: fix for sscanf use with save flags input.

evas: fix for sscanf use with save flags input.

Summary:
As 'flags' can be supplied by application, in case application is supplying
a big string(error case), it can cause crash in some version of glibc.

Setting maximum possible input (0x64) length as width specifier

Fix for static code analyzer warnings
- scanf without field width limits can crash with huge input data on some versions of libc

Signed-off-by: Godly T.Alias <godlytalias@yahoo.co.in>
Test Plan: Run SonarQube

Reviewers: cedric, raster, Princekrdubey, rajeshps

Reviewed By: cedric

Subscribers: jpeg

Differential Revision: https://phab.enlightenment.org/D5266

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>