stv0991: remove specific CONFIG_STV0991 configs

Remove the following STV0991 specific configs:
- CONFIG_STV0991 (never used, only defined in CONFIG_SYS_EXTRA_OPTIONS)
- CONFIG_STV0991_HZ (replaced by generic CONFIG_SYS_HZ)
- CONFIG_STV0991_HZ_CLOCK (replaced by generic CONFIG_SYS_HZ_CLOCK)

This patch allows to reduce the file config_whitelist.txt.

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/arch/arm/cpu/armv7/stv0991/timer.c b/arch/arm/cpu/armv7/stv0991/timer.c
index 07033ac..67764cc 100644
--- a/arch/arm/cpu/armv7/stv0991/timer.c
+++ b/arch/arm/cpu/armv7/stv0991/timer.c
@@ -18,7 +18,7 @@
 				(struct stv0991_cgu_regs *) (CGU_BASE_ADDR);
 
 #define READ_TIMER()	(readl(&gpt1_regs_ptr->cnt) & GPT_FREE_RUNNING)
-#define GPT_RESOLUTION	(CONFIG_STV0991_HZ_CLOCK / CONFIG_STV0991_HZ)
+#define GPT_RESOLUTION	(CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ)
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -67,7 +67,7 @@
 {
 	ulong tmo;
 	ulong start = get_timer_masked();
-	ulong tenudelcnt = CONFIG_STV0991_HZ_CLOCK / (1000 * 100);
+	ulong tenudelcnt = CONFIG_SYS_HZ_CLOCK / (1000 * 100);
 	ulong rndoff;
 
 	rndoff = (usec % 10) ? 1 : 0;
@@ -110,5 +110,5 @@
  */
 ulong get_tbclk(void)
 {
-	return CONFIG_STV0991_HZ;
+	return CONFIG_SYS_HZ;
 }