Undo hacks to meant to get around string formatting limitations

The new vuprintf makes unnecessary workarounds due to formatting
limitations. I checked grep output for whatever appeared to fit
but it's possible I missed some instances because they weren't
so obvious.

Also, this means sound settings can dynamically work with any
number of decimals rather than the current assumption of one or
two. Add an ipow() function to help and take advantage of dynamic
field width and precision. Consolidate string formatting of sound
settings.

Change-Id: I46caf534859dfd1916cd440cd25e5206b192fcd8

lib/fixedpoint/fixedpoint.c

@@ -211,6 +211,35 @@ long fp_sqrt(long x, unsigned int fracbits)
     return g;
 }
 
+/* raise an integer to an integer power */
+long ipow(long x, long y)
+{
+    /* y[k] = bit k of y, 0 or 1; k=0...n; n=|_ lg(y) _|
+     *
+     * x^y =  x^(y[0]*2^0 + y[1]*2^1 + ... + y[n]*2^n)
+     *     =  x^(y[0]*2^0) * x^(y[1]*2^1) * ... * x^(y[n]*2^n)
+     */
+    long a = 1;
+
+    if (y < 0 && x != -1)
+    {
+        a = 0; /* would be < 1 or +inf if x == 0 */
+    }
+    else
+    {
+        while (y)
+        {
+            if (y & 1)
+                a *= x;
+
+            y /= 2;
+            x *= x;
+        }
+    }
+
+    return a;
+}
+
 /**
  * Fixed point sinus using a lookup table
  * don't forget to divide the result by 16384 to get the actual sinus value