Fix a memory leak in fdread

[trix_juniper.net]

Summary

fdread.c doread
Free the memory allocated to trackbuf before exiting

Test Plan

Use clang's static analyzer, scan-build, to find the problem and then to verify the problem is resolved

[araujo]

Do you still have the log of analyzer before and after this patch?

[trix_juniper.net]

I will have to reproduce these, I will send it out asap.

[trix_juniper.net]

This is the before, the line number is a bit screwed up because i commented out my change.
The after has memory leak removed.

usr.sbin/fdread/fdread.c:134:2: warning: Value stored to 'argv' is never read

argv += optind;
^       ~~~~~~

usr.sbin/fdread/fdread.c:243:14: warning: The left expression of the compound assignment is an uninitialized value. The computed value will also be garbage

fdopts |= FDOPT_NOERROR;
~~~~~~ ^

usr.sbin/fdread/fdread.c:291:7: warning: Potential leak of memory pointed to by 'trackbuf'

if (!quiet) {
     ^~~~~

3 warnings generated.
scan-build: 3 bugs found.

[araujo]

Looks good to me! Do you want me commit it or you have src bit?

Best,

[trix_juniper.net]

Yes, please commit. I do not have commit perms.
Thank you,
Tom