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/mtd/nand/raw/octeontx_nand.c b/drivers/mtd/nand/raw/octeontx_nand.c
index 65a03d2..3b20685 100644
--- a/drivers/mtd/nand/raw/octeontx_nand.c
+++ b/drivers/mtd/nand/raw/octeontx_nand.c
@@ -24,6 +24,7 @@
 #include <linux/mtd/nand_bch.h>
 #include <linux/mtd/nand_ecc.h>
 #include <linux/mtd/rawnand.h>
+#include <linux/time.h>
 #include <asm/global_data.h>
 #include <asm/io.h>
 #include <asm/types.h>
@@ -291,7 +292,6 @@
 #define OCTEONTX_NAND_DRIVER_NAME	"octeontx_nand"
 
 #define NDF_TIMEOUT		1000	/** Timeout in ms */
-#define USEC_PER_SEC		1000000	/** Linux compatibility */
 #ifndef NAND_MAX_CHIPS
 # define NAND_MAX_CHIPS		8	/** Linux compatibility */
 #endif