Tinyalsa: standardize error message for wrong input value

Currently, if a user sets a mixer with a percentage value
greater than the maximum, tinyalsa does not inform the user
about this "error" and silently replaces the user's value
by the maximum. However, if a user sets a mixer with an
integer value greater than the maximum, tinyalsa informs
the user with an error.

This patch purpose is to define the same behaviour in both
quoted cases: user is informed through an error.

Change-Id: I79547758266d1eb08a65d7b1355ec9859f3b27bb
Signed-off-by: Baptiste Robert <baptistex.robert@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/mixer.c b/mixer.c
index b6c854f..057a271 100644
--- a/mixer.c
+++ b/mixer.c
@@ -259,14 +259,11 @@
 
 static int percent_to_int(struct snd_ctl_elem_info *ei, int percent)
 {
-    int range;
+    if ((percent > 100) || (percent < 0)) {
+        return -EINVAL;
+    }
 
-    if (percent > 100)
-        percent = 100;
-    else if (percent < 0)
-        percent = 0;
-
-    range = (ei->value.integer.max - ei->value.integer.min);
+    int range = (ei->value.integer.max - ei->value.integer.min);
 
     return ei->value.integer.min + (range * percent) / 100;
 }