Load correct module for linux and android when duplicates exist in minidump.

Load correct module for linux and android when duplicates exist in minidump.

Breakpad creates minidump files that can a module loaded multiple times. We found that when a process mmap's the object file for a library, this can confuse breakpad into creating multiple modules in the module list. This patch fixes the GetFilteredModules() to check the linux maps for permissions and use the one that has execute permissions. Typically when people mmap a file into memory they don't map it as executable. This helps people to correctly load minidump files for post mortem analysis.

Differential Revision: https://reviews.llvm.org/D86375