treewide: use linux/time.h for time conversion defines

Now that we have time conversion defines from in time.h there is no need
for each driver to define their own version.

Signed-off-by: Igor Prusov <ivprusov@salutedevices.com>
Reviewed-by: Svyatoslav Ryhel <clamor95@gmail.com> # tegra
Reviewed-by: Eugen Hristev <eugen.hristev@collabora.com> #at91
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org> #qcom geni
Reviewed-by: Stefan Bosch <stefan_b@posteo.net> #nanopi2
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/drivers/memory/stm32-fmc2-ebi.c b/drivers/memory/stm32-fmc2-ebi.c
index 212bb4f..a722a38 100644
--- a/drivers/memory/stm32-fmc2-ebi.c
+++ b/drivers/memory/stm32-fmc2-ebi.c
@@ -14,6 +14,7 @@
 #include <linux/err.h>
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
+#include <linux/time.h>
 
 /* FMC2 Controller Registers */
 #define FMC2_BCR1			0x0
@@ -90,8 +91,6 @@
 #define FMC2_BTR_DATLAT_MAX		0xf
 #define FMC2_PCSCNTR_CSCOUNT_MAX	0xff
 
-#define FMC2_NSEC_PER_SEC		1000000000L
-
 enum stm32_fmc2_ebi_bank {
 	FMC2_EBI1 = 0,
 	FMC2_EBI2,
@@ -279,7 +278,7 @@
 					     int cs, u32 setup)
 {
 	unsigned long hclk = clk_get_rate(&ebi->clk);
-	unsigned long hclkp = FMC2_NSEC_PER_SEC / (hclk / 1000);
+	unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
 
 	return DIV_ROUND_UP(setup * 1000, hclkp);
 }