Initialize token, temp, and value strings to empty.

==693==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x564634708d9e in token_cb /root/BUILD/cups-2.3.3op2/tools/ipptool.c:3330:2
    #1 0x7feb132dac54 in _ippFileParse /root/BUILD/cups-2.3.3op2/cups/ipp-file.c:184:12
    OpenPrinting#2 0x564634709456 in do_tests /root/BUILD/cups-2.3.3op2/tools/ipptool.c:1920:3
    OpenPrinting#3 0x56463470062e in main /root/BUILD/cups-2.3.3op2/tools/ipptool.c:671:12
    OpenPrinting#4 0x7feb12f615cf in __libc_start_call_main (/lib64/libc.so.6+0x295cf) (BuildId: 38347dcfe861b665e08e8b1263215f626f4e003c)
    OpenPrinting#5 0x7feb12f6167f in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2967f) (BuildId: 38347dcfe861b665e08e8b1263215f626f4e003c)
    OpenPrinting#6 0x564634664a34 in _start (/root/BUILD/cups-2.3.3op2/tools/ipptool+0x34a34) (BuildId: d57559e910bfffb79c75b95ff66855e9486eee5a)

SUMMARY: MemorySanitizer: use-of-uninitialized-value /root/BUILD/cups-2.3.3op2/tools/ipptool.c:3330:2 in token_cb
Exiting

When a new element of the options array is created, all fields of the cups_option_t structure (including value) are now initialized to zero. This ensures that when cups_compare_options is called to compare options, the structure contains no uninitialized bytes. MemorySanitizer will no longer report use-of-uninitialized-memory from this code path.


==661962==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x7f43488185f5 in cups_compare_options /home/tsudik/cups/test/cups/cups/cups/options.c:602:11
    #1 0x7f43488185f5 in cups_find_option /home/tsudik/cups/test/cups/cups/cups/options.c:642:17
    OpenPrinting#2 0x7f4348818063 in cupsAddOption /home/tsudik/cups/test/cups/cups/cups/options.c:91:14
    OpenPrinting#3 0x7f4348817de4 in cupsAddIntegerOption /home/tsudik/cups/test/cups/cups/cups/options.c:45:11
    OpenPrinting#4 0x7f43487fc551 in ippFileSetVar /home/tsudik/cups/test/cups/cups/cups/ipp-file.c:1136:24
    OpenPrinting#5 0x55fc5d3541ce in main /home/tsudik/cups/test/cups/cups/tools/ipptool.c:722:12
    OpenPrinting#6 0x7f43484295cf in __libc_start_call_main (/lib64/libc.so.6+0x295cf) (BuildId: 38347dcfe861b665e08e8b1263215f626f4e003c)
    OpenPrinting#7 0x7f434842967f in __libc_start_main@GLIBC_2.2.5 (/lib64/libc.so.6+0x2967f) (BuildId: 38347dcfe861b665e08e8b1263215f626f4e003c)
    OpenPrinting#8 0x55fc5d2b8bf4 in _start (/home/tsudik/cups/test/cups/cups/tools/ipptool+0x35bf4) (BuildId: 26bc6973ea67a83c8bb92151510715af79bc7b29)

SUMMARY: MemorySanitizer: use-of-uninitialized-value /home/tsudik/cups/test/cups/cups/cups/options.c:602:11 in cups_compare_options
Exiting