ARM linker: add --any_contingency option

When packing data into multiple regions using the `.ANY` directive,
the linker can accidentally overfill an area.

This doesn't normally happen because it defaults to
`--any_placement=worst_fit`, which puts data in the region with
most space.

When we prioritise regions with `.ANY1`/`.ANY2`, it may totally fill
an area, then fail to leave enough space for linker-generated veneers.
We've just seen this error with the new K64F linker map.

Adding `--any-contingency` makes it lower priority when a region is
98% full, avoiding this error.

The option should not have any effect on targets with scatter files
without prioritised `.ANY` directives.

tools/profiles/debug.json

@@ -26,7 +26,8 @@
         "asm": [],
         "c": ["-D__ASSERT_MSG", "-std=gnu11"],
         "cxx": ["-fno-rtti", "-std=gnu++14"],
-        "ld": ["--verbose", "--remove", "--show_full_path", "--legacyalign", "--keep=os_cb_sections"]
+        "ld": ["--verbose", "--remove", "--show_full_path", "--legacyalign",
+               "--any_contingency", "--keep=os_cb_sections"]
     },
     "ARM": {
         "common": ["-c", "--gnu", "-Otime", "--split_sections",
@@ -36,7 +37,7 @@
         "asm": [],
         "c": ["--md", "--no_depend_system_headers", "--c99", "-D__ASSERT_MSG"],
         "cxx": ["--cpp11", "--no_rtti", "--no_vla"],
-        "ld": ["--show_full_path", "--keep=os_cb_sections"]
+        "ld": ["--show_full_path", "--any_contingency", "--keep=os_cb_sections"]
     },
     "uARM": {
         "common": ["-c", "--gnu", "-Otime", "--split_sections",

tools/profiles/develop.json

@@ -24,7 +24,8 @@
         "asm": [],
         "c": ["-D__ASSERT_MSG", "-std=gnu11"],
         "cxx": ["-fno-rtti", "-std=gnu++14"],
-        "ld": ["--show_full_path", "--legacyalign", "--keep=os_cb_sections"]
+        "ld": ["--show_full_path", "--legacyalign", "--any_contingency",
+               "--keep=os_cb_sections"]
     },
     "ARM": {
         "common": ["-c", "--gnu", "-Otime", "--split_sections",
@@ -33,7 +34,7 @@
         "asm": [],
         "c": ["--md", "--no_depend_system_headers", "--c99", "-D__ASSERT_MSG"],
         "cxx": ["--cpp11", "--no_rtti", "--no_vla"],
-        "ld": ["--show_full_path", "--keep=os_cb_sections"]
+        "ld": ["--show_full_path", "--any_contingency", "--keep=os_cb_sections"]
     },
     "uARM": {
         "common": ["-c", "--gnu", "-Otime", "--split_sections",

tools/profiles/release.json

@@ -24,7 +24,8 @@
         "asm": [],
         "c": ["-D__ASSERT_MSG", "-std=gnu11"],
         "cxx": ["-fno-rtti", "-std=gnu++14"],
-        "ld": ["--show_full_path", "--legacyalign", "--keep=os_cb_sections"]
+        "ld": ["--show_full_path", "--legacyalign", "--any_contingency",
+               "--keep=os_cb_sections"]
     },
     "ARM": {
         "common": ["-c", "--gnu", "-Ospace", "--split_sections",
@@ -33,7 +34,7 @@
         "asm": [],
         "c": ["--md", "--no_depend_system_headers", "--c99", "-D__ASSERT_MSG"],
         "cxx": ["--cpp11", "--no_rtti", "--no_vla"],
-        "ld": ["--show_full_path",  "--keep=os_cb_sections"]
+        "ld": ["--show_full_path", "--any_contingency", "--keep=os_cb_sections"]
     },
     "uARM": {
         "common": ["-c", "--gnu", "-Ospace", "--split_sections",