zephyr: userspace: Fix compilation options

When CONFIG_USERSPACE enabled, the merging of global symbols ends with
SOF failures. The merging must be disabled when CONFIG_USERSPACE is set.

The patch fix also disabling -fno-inline-functions option which
works differently for clang, completely disabling function inlining.

Signed-off-by: Jaroslaw Stelter <Jaroslaw.Stelter@intel.com>

Author: jxstelter

zephyr/CMakeLists.txt

@@ -538,6 +538,10 @@ if (NOT CONFIG_COMPILER_INLINE_FUNCTION_OPTION)
 target_compile_options(SOF INTERFACE -fno-inline-functions)
 endif()
 
+if (CONFIG_USERSPACE)
+target_compile_options(SOF INTERFACE -mno-global-merge)
+endif()
+
 # SOF needs `typeof`, `__VA_ARGS__` and maybe other GNU C99
 # extensions. TODO other flags required ?
 target_compile_options(SOF INTERFACE $<$<COMPILE_LANGUAGE:C,ASM>: -std=gnu99>)