Remove dead CMake code (#1230)

Remove CMake statements that have no effect in math_brute_force.

set_source_files_properties without a list of files has no effect.

When MODULE_NAME is FOO,
set_source_files_properties(${MODULE_NAME}_SOURCES ...) sets the
properties of "FOO_SOURCES", not of the files listed in the variable
named FOO_SOURCES.

Signed-off-by: Marco Antognini <marco.antognini@arm.com>
diff --git a/test_conformance/math_brute_force/CMakeLists.txt b/test_conformance/math_brute_force/CMakeLists.txt
index 9643394..d8dfc40 100644
--- a/test_conformance/math_brute_force/CMakeLists.txt
+++ b/test_conformance/math_brute_force/CMakeLists.txt
@@ -34,15 +34,4 @@
     utility.cpp
 )
 
-if (NOT CMAKE_CL_64 AND NOT MSVC AND NOT ANDROID)
-set_source_files_properties(
-${MODULE_NAME}_SOURCES
-    COMPILE_FLAGS -march=i686)
-endif (NOT CMAKE_CL_64 AND NOT MSVC AND NOT ANDROID)
-
-if(CMAKE_COMPILER_IS_GNUCC)
-set_source_files_properties(
-        COMPILE_FLAGS -O0)
-endif(CMAKE_COMPILER_IS_GNUCC)
-
 include(../CMakeCommon.txt)