simpleperf: fix string operand support in --tp-filter.

Kernel < 4.19 doesn't support quotes in string operands, while kernel
>= 4.19 requires quotes in string operands.
This CL supports both cases in --tp-filter option, and modifies quotes
for string operands based on the kernel version.

Bug: 160900181
Test: run simpleperf_unit_test.
Change-Id: Icede9fde2ae739189a6120c969bdfb6bf5f28456
8 files changed