Use explicit .c_str() for hidl_string

hidl_string no longer will provide an implicit cast to const char* as it
interfers with other expected behaviors of the class.  It now emulated
std::string in requiring a call to .c_str() to get the same behavior.

Bug:  36532780
Test:  Build the tree
Change-Id: I5d672f4a215f4272b7d5d87772667352cf2fb317
1 file changed
tree: e6eaf1e58e209fa506a6573909e5391467402651
  1. include/
  2. libril/
  3. librilutils/
  4. reference-ril/
  5. rild/
  6. CleanSpec.mk