ApexInfo doesn't pass MinSdkVersion as string, but as ApiLevel

ApexInfo is not part of the properties struct. It can handle structs
having private fields.

Bug: 1663140
Test: m
Change-Id: Ib07d4410f0ce187c9de347da34b84b814b2eb537
diff --git a/cc/cc.go b/cc/cc.go
index bef49b8..7f69d56 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -2499,7 +2499,7 @@
 	c.apexSdkVersion = android.FutureApiLevel
 	apexInfo := ctx.Provider(android.ApexInfoProvider).(android.ApexInfo)
 	if !apexInfo.IsForPlatform() {
-		c.apexSdkVersion = apexInfo.MinSdkVersion(ctx)
+		c.apexSdkVersion = apexInfo.MinSdkVersion
 	}
 
 	if android.InList("hwaddress", ctx.Config().SanitizeDevice()) {