Remove uses of secp244k1

Remove all code guarded by `PSA_WANT_ECC_SECP_K1_224`, which is not and will
not be implemented. (It would be K1_225 anyway, but we don't intend to
implement it anyway.)

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/scripts/config.py b/scripts/config.py
index db2bc57..3508ce4 100755
--- a/scripts/config.py
+++ b/scripts/config.py
@@ -60,13 +60,8 @@
     'PSA_WANT_KEY_TYPE_RSA_KEY_PAIR'
 ])
 
-PSA_UNSTABLE_FEATURE = frozenset([
-    'PSA_WANT_ECC_SECP_K1_224'
-])
-
 EXCLUDE_FROM_CRYPTO = PSA_UNSUPPORTED_FEATURE | \
-                      PSA_DEPRECATED_FEATURE | \
-                      PSA_UNSTABLE_FEATURE
+                      PSA_DEPRECATED_FEATURE
 
 # The goal of the full configuration is to have everything that can be tested
 # together. This includes deprecated or insecure options. It excludes:
@@ -114,7 +109,6 @@
     'MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE', # only relevant for embedded devices
     *PSA_UNSUPPORTED_FEATURE,
     *PSA_DEPRECATED_FEATURE,
-    *PSA_UNSTABLE_FEATURE
 ])
 
 def is_seamless_alt(name):
@@ -367,8 +361,6 @@
 
         if name in PSA_UNSUPPORTED_FEATURE:
             raise ValueError(f'Feature is unsupported: \'{name}\'')
-        if name in PSA_UNSTABLE_FEATURE:
-            raise ValueError(f'Feature is unstable: \'{name}\'')
 
         if name not in self.settings:
             self._get_configfile().templates.append((name, '', '#define ' + name + ' '))
@@ -417,8 +409,6 @@
         if configfile == self.crypto_configfile:
             if name in PSA_UNSUPPORTED_FEATURE:
                 raise ValueError(f'Feature is unsupported: \'{name}\'')
-            if name in PSA_UNSTABLE_FEATURE:
-                raise ValueError(f'Feature is unstable: \'{name}\'')
 
             # The default value in the crypto config is '1'
             if not value and re.match(self._crypto_regexp, name):