fiber/switch_context_riscv.S: disable executable stack

Like it is done for the other assembly files, add the GNU-stack note.

Signed-off-by: Andrei Horodniceanu <a.horodniceanu@proton.me>

Author: the-horo

runtime/druntime/src/core/thread/fiber/switch_context_riscv.S

@@ -6,6 +6,18 @@
  * Authors:   Denis Feklushkin
  */
 
+#if (__linux__ || __FreeBSD__ || __NetBSD__ || __OpenBSD__ || __DragonFly__) && __ELF__
+/*
+ * Mark the resulting object file as not requiring execution permissions on
+ * stack memory. The absence of this section would mark the whole resulting
+ * library as requiring an executable stack, making it impossible to
+ * dynamically load druntime on several Linux platforms where this is
+ * forbidden due to security policies.
+ */
+.section .note.GNU-stack,"",%progbits
+#endif
+
+
 #if defined(__riscv)
 
 // For save/load a register in memory, regardless of the size of machine register bit size