Update -ld-path flag

Upstream dependencies:
swiftlang/swift#68495
swiftlang/swift-driver#1441

Author: kabiroberai

Sources/PackageModel/UserToolchain.swift

@@ -331,7 +331,7 @@ public final class UserToolchain: Toolchain {
         var swiftCompilerFlags = swiftSDK.toolset.knownTools[.swiftCompiler]?.extraCLIOptions ?? []
 
         if let linker = swiftSDK.toolset.knownTools[.linker]?.path {
-            swiftCompilerFlags += ["--ld-path=\(linker)"]
+            swiftCompilerFlags += ["-ld-path=\(linker)"]
         }
 
         guard let sdkDir = swiftSDK.pathsConfiguration.sdkRootPath else {

Tests/BuildTests/BuildPlanTests.swift

@@ -3689,7 +3689,7 @@ final class BuildPlanTests: XCTestCase {
         let exeCompileArguments = try result.target(for: "exe").swiftTarget().compileArguments()
         let exeCompileArgumentsPattern: [StringPattern] = [
             jsonFlag(tool: .swiftCompiler),
-            "--ld-path=/fake/toolchain/usr/bin/linker",
+            "-ld-path=/fake/toolchain/usr/bin/linker",
             "-g", cliFlag(tool: .swiftCompiler),
             .anySequence,
             "-Xcc", jsonFlag(tool: .cCompiler), "-Xcc", "-g", "-Xcc", cliFlag(tool: .cCompiler),
@@ -3714,7 +3714,7 @@ final class BuildPlanTests: XCTestCase {
         let exeLinkArguments = try result.buildProduct(for: "exe").linkArguments()
         let exeLinkArgumentsPattern: [StringPattern] = [
             jsonFlag(tool: .swiftCompiler),
-            "--ld-path=/fake/toolchain/usr/bin/linker",
+            "-ld-path=/fake/toolchain/usr/bin/linker",
             "-g", cliFlag(tool: .swiftCompiler),
             .anySequence,
             "-Xlinker", jsonFlag(tool: .linker), "-Xlinker", cliFlag(tool: .linker),