vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs

All calls of these functions are already gated behind CONFIG_TIME_NS. The
compiler will already optimize them away if time namespaces are disabled.

Drop the unnecessary stubs.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-4-d9b65750e49f@linutronix.de

Author: t-8ch

lib/vdso/gettimeofday.c

@@ -108,8 +108,6 @@ bool vdso_get_timestamp(const struct vdso_time_data *vd, const struct vdso_clock
 	return true;
 }
 
-#ifdef CONFIG_TIME_NS
-
 #ifdef CONFIG_GENERIC_VDSO_DATA_STORE
 static __always_inline
 const struct vdso_time_data *__arch_get_vdso_u_timens_data(const struct vdso_time_data *vd)
@@ -149,20 +147,6 @@ bool do_hres_timens(const struct vdso_time_data *vdns, const struct vdso_clock *
 
 	return true;
 }
-#else
-static __always_inline
-const struct vdso_time_data *__arch_get_vdso_u_timens_data(const struct vdso_time_data *vd)
-{
-	return NULL;
-}
-
-static __always_inline
-bool do_hres_timens(const struct vdso_time_data *vdns, const struct vdso_clock *vcns,
-		    clockid_t clk, struct __kernel_timespec *ts)
-{
-	return false;
-}
-#endif
 
 static __always_inline
 bool do_hres(const struct vdso_time_data *vd, const struct vdso_clock *vc,
@@ -204,7 +188,6 @@ bool do_hres(const struct vdso_time_data *vd, const struct vdso_clock *vc,
 	return true;
 }
 
-#ifdef CONFIG_TIME_NS
 static __always_inline
 bool do_coarse_timens(const struct vdso_time_data *vdns, const struct vdso_clock *vcns,
 		      clockid_t clk, struct __kernel_timespec *ts)
@@ -233,14 +216,6 @@ bool do_coarse_timens(const struct vdso_time_data *vdns, const struct vdso_clock
 
 	return true;
 }
-#else
-static __always_inline
-bool do_coarse_timens(const struct vdso_time_data *vdns, const struct vdso_clock *vcns,
-		      clockid_t clk, struct __kernel_timespec *ts)
-{
-	return false;
-}
-#endif
 
 static __always_inline
 bool do_coarse(const struct vdso_time_data *vd, const struct vdso_clock *vc,