Remove dependency on cmsis_device

The applications doesn't need the cmsis device dependency. Remove it and
add the explicit headers that are required to access assembler defines.

Change-Id: I959b60e0ca150a75145319df207cfeb6361f0022
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3e14fe0..99d829c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,4 +62,4 @@
 add_subdirectory(drivers)
 
 # Merge libraries into static library
-target_link_libraries(ethosu_core INTERFACE tflu cmsis_core cmsis_device ethosu_applications ethosu_drivers)
+target_link_libraries(ethosu_core INTERFACE tflu cmsis_core ethosu_applications ethosu_drivers)