[FIR] Add SourceSet.generatedDir() and use it in build.gradle.kts

compiler/fir/checkers/build.gradle.kts

@@ -20,7 +20,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
     "test" { none() }
 }

compiler/fir/checkers/checkers.js/build.gradle.kts

@@ -22,7 +22,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
     "test" { none() }
 }

compiler/fir/checkers/checkers.jvm/build.gradle.kts

@@ -23,7 +23,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
     "test" { none() }
 }

compiler/fir/checkers/checkers.native/build.gradle.kts

@@ -22,7 +22,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
     "test" { none() }
 }

compiler/fir/tree/build.gradle.kts

@@ -16,7 +16,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
 }
 

compiler/ir/ir.tree/build.gradle.kts

@@ -19,7 +19,7 @@ dependencies {
 sourceSets {
     "main" {
         projectDefault()
-        this.java.srcDir("gen")
+        generatedDir()
     }
     "test" {}
 }