x86: enable PIE for dynamically linked executables
x86: enable PIE for dynamically linked executables

Compile all x86 programs on Android with -fPIE and -pie. This enables
PIE (Position Independent Executables), which helps protect Android
applications from exploitation due to memory management bugs.

Note 1: PIE *static* executables are not supported at this time and
require additional linker changes.

Note 2: This change compliments 026a85b129e4540a4d8d40aace47aa0c69f609da,
which was the exact same change, except for ARM.

Testing: Rebuilt the tree completely from scratch, and verified
that the system boots and basic functionality works in the emulator.

Change-Id: I990064c37da3d857e663b27f31fee05f689a2824

xorware/android_build,see4ri/lolili,xorware/android_build,fallouttester/platform_manifest,Hybrid-Power/startsync,pranav01/platform_manifest,knone1/platform_manifest,ND-3500/platform_manifest,RR-msm7x30/platform_manifest,xorware/android_build,xorware/android_build,xorware/android_build,hagar006/platform_manifest