3rdparty: Fix Makefile coding conventions

3rdparty/Makefile.inc

@@ -1 +1,2 @@
-include ../3rdparty/everest/Makefile.inc
+include ../3rdparty/everest/Makefile.inc
+

3rdparty/everest/Makefile.inc

@@ -16,3 +16,4 @@ THIRDPARTY_OBJECTS+=../3rdparty/everest/library/legacy/Hacl_Curve25519.o \
 	../3rdparty/everest/library/kremlib/FStar_UInt128_extracted.o
 endif
 endif
+

tests/scripts/check-files.py

@@ -144,6 +144,7 @@ class TabIssueTracker(LineIssueTracker):
     heading = "Tabs present:"
     files_exemptions = frozenset([
         "Makefile",
+        "Makefile.inc",
         "generate_visualc_files.pl",
     ])
 
@@ -181,7 +182,7 @@ class IntegrityChecker(object):
         self.setup_logger(log_file)
         self.files_to_check = (
             ".c", ".h", ".sh", ".pl", ".py", ".md", ".function", ".data",
-            "Makefile", "CMakeLists.txt", "ChangeLog"
+            "Makefile", "Makefile.inc", "CMakeLists.txt", "ChangeLog"
         )
         self.excluded_directories = ['.git', 'mbed-os']
         self.excluded_paths = list(map(os.path.normpath, [