condor: enable building android boot image for 2ndstage boot
condor: mkbootimg: fix warning
this was the warning:
target/condor/tools/mkbootimg/mkbootimg.c: In function ‘main’:
target/condor/tools/mkbootimg/mkbootimg.c:253:9: warning: assignment discards ‘const’ qualifier from pointer target type [enabled by default]
     sha = SHA_final(&ctx);
         ^