Allow configuration of the CONFIG_NO_ROAMING flag in Android.bp

Bug: 364352776, 350971011
Test: mmma wpa_supplicant
Change-Id: I23fc8911f481a921bd663ab8672b1f4046cbc8bc
diff --git a/wpa_supplicant/Android.bp b/wpa_supplicant/Android.bp
index 8c50031..7fb7cd2 100644
--- a/wpa_supplicant/Android.bp
+++ b/wpa_supplicant/Android.bp
@@ -129,7 +129,6 @@
         "-DCONFIG_NO_RADIUS",
         "-DCONFIG_NO_RADIUS",
         "-DCONFIG_NO_RANDOM_POOL",
-        "-DCONFIG_NO_ROAMING",
         "-DCONFIG_NO_VLAN",
         "-DCONFIG_OFFCHANNEL",
         "-DCONFIG_OWE",
@@ -199,6 +198,10 @@
             any @ driver: ["-D" + driver],
             // Flag is optional, so no default value provided.
             default: [],
+        }) +
+        select(soong_config_variable("wpa_supplicant", "roaming"), {
+            true: [],
+            default: ["-DCONFIG_NO_ROAMING"],
         }),
     // Similar to suppressing clang compiler warnings, here we
     // suppress clang-tidy warnings to reduce noises in Android build.log.