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/rangeFolding.kt

@@ -0,0 +1,76 @@
+// FILE: 1.kt
+package test
+
+inline fun f() {}
+inline fun g() {}
+inline fun h() {}
+
+inline fun together() {
+    f() // new range 1.kt:N -> 1.kt:4
+    h() // new range 1.kt:N+1 -> 1.kt:6 because of different call site
+    g() // new range 1.kt:N+2 -> 1.kt:5 for the same reason
+}
+
+// FILE: 2.kt
+import test.*
+
+fun box(): String {
+    // 1. new range 2.kt:N -> 1.kt:9
+    // 2. new range 2.kt:N+1 -> 1.kt:4
+    // 3. extend to 2.kt:N+1..N+7 -> 1.kt:4..10 and use N+7 for 1.kt:10
+    // 4. use N+2 for 1.kt:5
+    // 5. extend to 2.kt:N+1..N+8 -> 1.kt:4..11 and use N+8 for 1.kt:11
+    // 6. use N+3 for 1.kt:6
+    // 7. extend to 2.kt:N+1..N+9 -> 1.kt:4..12 and use N+9 for 1.kt:12
+    // steps 4 and 6 *should not* create new ranges
+    together()
+    return "OK"
+}
+
+// FILE: 1.smap
+SMAP
+1.kt
+Kotlin
+*S Kotlin
+*F
++ 1 1.kt
+test/_1Kt
+*L
+1#1,14:1
+4#1:15
+6#1:16
+5#1:17
+*E
+*S KotlinDebug
+*F
++ 1 1.kt
+test/_1Kt
+*L
+9#1:15
+10#1:16
+11#1:17
+*E
+
+// FILE: 2.smap
+SMAP
+2.kt
+Kotlin
+*S Kotlin
+*F
++ 1 2.kt
+_2Kt
++ 2 1.kt
+test/_1Kt
+*L
+1#1,17:1
+9#2:18
+4#2,9:19
+*E
+*S KotlinDebug
+*F
++ 1 2.kt
+_2Kt
+*L
+13#1:18
+13#1,9:19
+*E