[krbdev.mit.edu #3217] move strlen out of loop to improve performance

[Alexandra Ellwood via RT]

krb5/src/appl/gssftp/ftp/main.c:604:   for (k=0; k < strlen(c->c_name); k++) {
krb5/src/kadmin/dbutil/util.c:50:   for ( i = 0; i < strlen(s1); i++) {