Clean up showmap prints

This change refactors some print statements that varied on the selected
output format into their own functions (e.g. print_vmainfo,
print_vmainfo_totals, print_header) for clarity. This change also
realigns some raw text output.

This change also:
- cleans up get_vma_name() by removing explicit std::string
  instantiations and using consistent variable naming.
- replaces the const char* progname argument in usage() with a hardcoded
  "showmap" (originally suggested in aosp/1056769)

showmap -a -v <pidof system_server>:
Before: go/paste/6425435024916480
After:  go/paste/6047817339502592

Test: Manually verified that showmap output (with different options and
      output formats) still return correct output.
Bug: 229147699
Change-Id: I8bdec4783379fddfb3458b450a67d8a4554078d2
1 file changed