soc: sifive: l2 cache: Eliminate an unsigned zero compare warning

GCC warns about this comparison, which is unnecessary.
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

drivers/soc/sifive/sifive_l2_cache.c

@@ -51,7 +51,7 @@ static ssize_t l2_write(struct file *file, const char __user *data,
 
 	if (kstrtouint_from_user(data, count, 0, &val))
 		return -EINVAL;
-	if ((val >= 0 && val < 0xFF) || (val >= 0x10000 && val < 0x100FF))
+	if ((val < 0xFF) || (val >= 0x10000 && val < 0x100FF))
 		writel(val, l2_base + SIFIVE_L2_ECCINJECTERR);
 	else
 		return -EINVAL;