Enforce valid APF versions (0, 2, 3, 4, 6000, 6100)

This commit adds a check to enforce that reported APF versions are
either 0 (indicating no support) or one of the officially valid
versions: 2, 3, 4, 6000 or 6100. This ensures consistency and prevents
issues arising from device using unsupported APF versions.

Test: TH
Flag: EXEMPT bugfix
Change-Id: Icdefa89fae590ec78146df4cbd2c683b5d8258f7

tests/cts/net/src/android/net/cts/ApfIntegrationTest.kt

@@ -405,6 +405,8 @@ class ApfIntegrationTest {
     )
     @Test
     fun testApfCapabilities() {
+        // If APF is supported, the version must be valid.
+        assertThat(caps.apfVersionSupported).isAnyOf(0, 2, 3, 4, 6000, 6100)
         // APF became mandatory in Android 14 VSR.
         val vsrApiLevel = getVsrApiLevel()
         assume().that(vsrApiLevel).isAtLeast(34)