[JVM_IR] Generate line numbers in synthetic bridges.

The current backend does that for some bridges. We do it consistently
for all bridges.

The line number used differs. For the JVM_IR backend, we use the
line number of the class to which the bridge is added. For the
JVM backend, that does not appear to be the case for bridges
in lambdas. I prefer the line number for a lambda invoke bridge
to be the line for the lambda instead os some surrounding class.

compiler/testData/debug/stepping/initBlocksCompanion.kt

@@ -30,8 +30,6 @@ fun box() {
     A.s
 }
 
-// JVM backend has extra steps for getX and getS.
-
 // LINENUMBERS
 // test.kt:29 box
 // test.kt:7 <clinit>
@@ -46,14 +44,10 @@ fun box() {
 // test.kt:21 <clinit>
 // test.kt:22 <clinit>
 // test.kt:11 getX
-// LINENUMBERS JVM
 // test.kt:11 getX
-// LINENUMBERS
 // test.kt:29 box
 // test.kt:30 box
 // test.kt:5 getS
-// LINENUMBERS JVM
 // test.kt:5 getS
-// LINENUMBERS
 // test.kt:30 box
 // test.kt:31 box