refine lzma ramdisk type check

We meet this OOM after PR 66:
  https://github.com/cfig/Android_boot_image_editor/pull/66
Need to harden ZipHelper by catching OOM error when trying lzma.

helper/src/main/kotlin/cfig/helper/ZipHelper.kt

@@ -213,6 +213,14 @@ class ZipHelper {
             this.closeArchiveEntry()
         }
 
+        /*
+        LZMACompressorInputStream() may raise OOM sometimes, like this:
+            Caused by: java.lang.OutOfMemoryError: Java heap space
+            at org.tukaani.xz.ArrayCache.getByteArray(Unknown Source)
+            at org.tukaani.xz.lz.LZDecoder.<init>(Unknown Source)
+            at org.tukaani.xz.LZMAInputStream.initialize(Unknown Source)
+        So we catch it explicitly.
+         */
         fun isLzma(compressedFile: String): Boolean {
             return try {
                 FileInputStream(compressedFile).use { fis ->
@@ -222,6 +230,8 @@ class ZipHelper {
                 true
             } catch (e: IOException) {
                 false
+            } catch (e: OutOfMemoryError) {
+                false
             }
         }