Tegra: replace ASM signed tests with unsigned

Replace the occurrences of signed condition codes where it was
unnecessary by an unsigned test as the unsigned tests allow the full
range of unsigned values to be used without inverting the result with
some large operands.

This reverts commit ee2c909947e0a9c4a2562689a7bfc863bc4794f9.

Change-Id: Ibaa5e8dfae6ad65bada3cda5f683d181fee37e53
Acked-by: Varun Wadekar <vwadekar@nvidia.com>
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
diff --git a/plat/nvidia/tegra/common/aarch64/tegra_helpers.S b/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
index 70a7f3a..308753e 100644
--- a/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
+++ b/plat/nvidia/tegra/common/aarch64/tegra_helpers.S
@@ -289,7 +289,7 @@
 	mov	x2, #BL31_SIZE
 _loop16:
 	cmp	x2, #16
-	b.lt	_loop1
+	b.lo	_loop1
 	ldp	x3, x4, [x1], #16
 	stp	x3, x4, [x0], #16
 	sub	x2, x2, #16