SPARK-27259 Fix

Incorporating comment of modifying the validation to be `length >= -1`

Author: prasha2

core/src/main/scala/org/apache/spark/rdd/InputFileBlockHolder.scala

@@ -76,6 +76,7 @@ private[spark] object InputFileBlockHolder {
   def set(filePath: String, startOffset: Long, length: Long): Unit = {
     require(filePath != null, "filePath cannot be null")
     require(startOffset >= 0, s"startOffset ($startOffset) cannot be negative")
+	require(length >= -1, s"length ($length) cannot be smaller than -1")
     inputBlock.get().set(new FileBlock(UTF8String.fromString(filePath), startOffset, length))
   }