meta-monitor.c: Allow 75% scaling once more.

This was possible in muffin <= 5.2 but was mistakenly disallowed
in 5.4.

Author: mtwebster

src/backends/meta-monitor.c

@@ -33,7 +33,7 @@
 
 #define SCALE_FACTORS_PER_INTEGER 4
 #define SCALE_FACTORS_STEPS (1.0 / (float) SCALE_FACTORS_PER_INTEGER)
-#define MINIMUM_SCALE_FACTOR 1.0f
+#define MINIMUM_SCALE_FACTOR 0.74f
 #define MAXIMUM_SCALE_FACTOR 4.0f
 #define MINIMUM_LOGICAL_AREA (800 * 480)
 #define MAXIMUM_REFRESH_RATE_DIFF 0.001