stacktrace: Print binary even if symbol name found

[Bojun-Seo]

Print executable or library name and its' offset, even if heaptrace found the symbol name and its' offset. User could find the location of the symbol easily with this patch.

Changed the way to report. Consider, A: symbol name B: symbol offset C: executable or library name D: executable or library offset

In case of symbol name found: A +B (C +D) In case of symbol name not found: (C +D)

Without this commit:

 0 [0x7f67b66bf60f] malloc +0x1f
 1 [0x5645cb2cc1bf] main +0x5
 2 [0x7f67b64b2d90] /lib/x86_64-linux-gnu/libc.so.6 (+0x29d90)
 3 [0x7f67b64b2e40] __libc_start_main +0x20
 4 [0x5645cb2cc0e5] _start +0x9

With this commit:

 0 [0x7f060eb2a60f] malloc +0x1f (./libheaptrace.so +0x460f)
 1 [0x5603bfdb11bf] main +0x5 (samples/sample_leak.out +0x11bf)
 2 [0x7f060e91dd90] (/lib/x86_64-linux-gnu/libc.so.6 +0x29d90)
 3 [0x7f060e91de40] __libc_start_main +0x20 (/lib/x86_64-linux-gnu/libc.so.6 +0x29e40)
 4 [0x5603bfdb10e5] _start +0x9 (samples/sample_leak.out +0x10e5)

User could easily know that __libc_start_main function can be found on /lib/x86_64-linux-gnu/libc.so.6