Disable stack protector features when cross compiling

When cross-compiling this for remarkable using the poky toolchain
this results in linker errors with stack protector: libssp_nonshared.a
not found

Author: gergap

src/CMakeLists.txt

@@ -15,7 +15,7 @@ if(NOT TOKEN_AUTH_ONLY)
 endif()
 
 if(NOT MSVC)
-  if(NOT (CMAKE_SYSTEM_PROCESSOR MATCHES "^(alpha|parisc|hppa)"))
+  if(NOT (CMAKE_SYSTEM_PROCESSOR MATCHES "^(alpha|parisc|hppa)") AND NOT CMAKE_CROSSCOMPILING)
     if((CMAKE_CXX_COMPILER_ID MATCHES "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9))
       set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fstack-protector --param=ssp-buffer-size=4")
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fstack-protector --param=ssp-buffer-size=4")