Add -fPIC flag when building sp3 library

This will support the sp3 library built on one gcc version to be
compatible with another gcc version.

Change-Id: If67714bd63376dc781c56ed025be335fe54b2ba5
Signed-off-by: Yong Zhao <Yong.Zhao@amd.com>

tests/kfdtest/sp3/lib_helper/CMakeLists_sp3.txt

@@ -68,7 +68,7 @@ message( STATUS "PROJECT_SOURCE_DIR:" ${PROJECT_SOURCE_DIR} )
 #  message(STATUS "${file}")
 #endforeach()
 
-set ( CMAKE_C_FLAGS "-DSP3_STATIC_LIB -Wno-error -DPUBLIC_RELEASE -DLITTLEENDIAN_CPU" )
+set ( CMAKE_C_FLAGS "-DSP3_STATIC_LIB -Wno-error -DPUBLIC_RELEASE -DLITTLEENDIAN_CPU -fPIC" )
 
 add_library(amdsp3 ${SRC_FILES})