[klibc] klibc warnings

[Sam Ravnborg]

Noticed a few warnings while playing with klibc.
Would be nice to have them fixed before pushing
for inclusion in the kernel.

usr/lib/readdir.c: In function `readdir':
usr/lib/readdir.c:54: warning: use of cast expressions as lvalues is deprecated

usr/lib/qsort.c: In function `qsort':
usr/lib/qsort.c:33: warning: use of cast expressions as lvalues is deprecated

usr/lib/sha1hash.c: In function `main':
usr/lib/sha1hash.c:292: warning: unused variable `j'

s/lib/klibc/g in the above to get right path.

	Sam