cmake: fix native build on arm

uname -m on 32bit Arm platforms (little endian) report a machine string
like armv5tejl, armv7l or armv8l.

A native build on these machines fail:

CMake Error at lib/processor/CMakeLists.txt:1 (add_subdirectory):
  add_subdirectory given source "armv8l" which is not an existing directory.

Set PROJECT_PROCESSOR to arm on these machines.

Signed-off-by: Benedikt Spranger <[email protected]>

Author: bene42

cmake/options.cmake

@@ -49,6 +49,11 @@ string (TOLOWER ${CMAKE_SYSTEM_PROCESSOR} PROJECT_PROCESSOR)
 if("${PROJECT_PROCESSOR}" STREQUAL "arm64")
   set (PROJECT_PROCESSOR "aarch64")
 endif()
+
+if("${PROJECT_PROCESSOR}" MATCH "armv[4-8].*l")
+  set (PROJECT_PROCESSOR "arm")
+endif()
+
 string (TOUPPER ${PROJECT_PROCESSOR}      PROJECT_PROCESSOR_UPPER)
 string (TOLOWER ${MACHINE}                PROJECT_MACHINE)
 string (TOUPPER ${MACHINE}                PROJECT_MACHINE_UPPER)