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/rangeFoldingInClass.kt

@@ -0,0 +1,100 @@
+// FILE: 1.kt
+package test
+
+object A { inline fun f() {} }
+object B { inline fun g() {} }
+object C { inline fun h() {} }
+
+object D {
+    inline fun together() {
+        A.f()
+        C.h()
+        B.g()
+    }
+}
+
+// FILE: 2.kt
+import test.*
+
+object X {
+    // Unlike `rangeFolding.kt`, the calls in `D.together` refer to different
+    // classes which are reflected in the SMAP, so they cannot be joined into
+    // a single range even in `X.foo`; neither can lines corresponding to
+    // `D.together` because they do not form an uninterrupted range.
+    fun foo() = D.together()
+}
+
+fun box(): String {
+    X.foo()
+    return "OK"
+}
+
+// FILE: 1.smap
+SMAP
+1.kt
+Kotlin
+*S Kotlin
+*F
++ 1 1.kt
+test/D
++ 2 1.kt
+test/A
++ 3 1.kt
+test/C
++ 4 1.kt
+test/B
+*L
+1#1,16:1
+4#2:17
+6#3:18
+5#4:19
+*E
+*S KotlinDebug
+*F
++ 1 1.kt
+test/D
+*L
+10#1:17
+11#1:18
+12#1:19
+*E
+
+// FILE: 2.smap
+SMAP
+2.kt
+Kotlin
+*S Kotlin
+*F
++ 1 2.kt
+X
++ 2 1.kt
+test/D
++ 3 1.kt
+test/A
++ 4 1.kt
+test/C
++ 5 1.kt
+test/B
+*L
+1#1,17:1
+10#2:18
+11#2:20
+12#2:22
+13#2:24
+4#3:19
+6#4:21
+5#5:23
+*E
+*S KotlinDebug
+*F
++ 1 2.kt
+X
+*L
+9#1:18
+9#1:20
+9#1:22
+9#1:24
+9#1:19
+9#1:21
+9#1:23
+*E