build: switch global_arguments to project_arguments

When 'oem-ibm' is enabled there are compile flags that
need to be applied across all files in this project.  To
do that, 'add_project_arguments' should be used and not
'add_global_arguments' because:

    1. These compile flags should only affect this project.
    2. Meson subprojects may not update global arguments.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I360b6e03d37d6dfeab0085253992a443543e94a6