JVM: fix SMAP range extension logic

If `mapLineNumber` was called in non-monotonic order, e.g. N then N+2
then N+1, the first two calls created a range that spans [N; N+2] but
the third call did not reuse it.

compiler/testData/codegen/boxInline/smap/interleavedFiles.kt

@@ -36,12 +36,10 @@ test/_1Kt
 4#1:19
 7#1:21
 8#1:23
-4#1,6:24
-10#1:31
+4#1,7:24
 4#2:18
 4#2:20
 4#2:22
-4#2:30
 *E
 *S KotlinDebug
 *F
@@ -51,10 +49,8 @@ _2Kt
 8#1:19
 13#1:21
 13#1:23
-13#1,6:24
-13#1:31
+13#1,7:24
 7#1:18
 9#1:20
 13#1:22
-13#1:30
 *E