Fix target test

Author: martin-frbg

cmake/os.cmake

@@ -85,10 +85,12 @@ if (X86)
 endif ()
 
 if (DYNAMIC_ARCH)
+if (TARGET)
 if (${TARGET} STREQUAL "GENERIC")
   set(NO_EXPRECISION 1)
 endif ()
 endif ()
+endif ()
 
 if (UTEST_CHECK)
   set(CCOMMON_OPT "${CCOMMON_OPT} -DUTEST_CHECK")