MINOR: initcall: Don't forget to define the __start/stop_init_##stg symbols.

When creating a new initcall, don't forget to define the symbols, as it may
not be done automatically and that would lead to undefined symbols.

This should be backported to 1.9.

include/common/initcall.h

@@ -98,7 +98,11 @@ struct initcall {
  * as a pointer (args are cast to (void*)). Do not use this macro directly,
  * use INITCALL{0..3}() instead.
  */
+#define __GLOBL1(sym)   __asm__(".globl " #sym)
+#define __GLOBL(sym)    __GLOBL1(sym)
 #define __DECLARE_INITCALL(stg, linenum, function, a1, a2, a3)     \
+        __GLOBL(__start_init_##stg );                              \
+	__GLOBL(__stop_init_##stg );                               \
 	static const struct initcall *__initcb_##linenum           \
 	    __attribute__((__used__,HA_SECTION(stg))) =            \
 	        (stg < STG_SIZE) ? &(const struct initcall) {      \
@@ -108,6 +112,7 @@ struct initcall {
 		.arg3 = (void *)(a3),                              \
 	} : NULL
 
+
 #else // USE_OBSOLETE_LINKER
 
 /* Declare a static constructor function to register a static descriptor for