radeon/llvm: Free elf_buffer after use

Prevents a memory leak.

v2: Remove null check

CC: "10.0" <mesa-stable@lists.freedesktop.org>
diff --git a/src/gallium/drivers/radeon/radeon_llvm_emit.c b/src/gallium/drivers/radeon/radeon_llvm_emit.c
index d2e5642..92e7dbc 100644
--- a/src/gallium/drivers/radeon/radeon_llvm_emit.c
+++ b/src/gallium/drivers/radeon/radeon_llvm_emit.c
@@ -176,6 +176,7 @@
 	if (elf){
 		elf_end(elf);
 	}
+	FREE(elf_buffer);
 	LLVMDisposeMemoryBuffer(out_buffer);
 	LLVMDisposeTargetMachine(tm);
 	return 0;