BootAnimation: remove superfluous null check for mAnimation

The null check added in I603da080b1732a436a10dbaca6f2be9f158124dc makes
our static analyzer suspect that the call to
`playAnimation(*mAnimation)` dereferences null. The beginning of this
function establishes a non-null value for `mAnimation`, which is used
unconditionally throughout the function. Hence, this condition seems
unnecessary.

Bug: None
Test: TreeHugger
Change-Id: I0575df17df7f7e3018d99cafd9dcfcd3c10e5fbc

cmds/bootanimation/BootAnimation.cpp

@@ -1339,7 +1339,7 @@ bool BootAnimation::movie() {
         mTimeCheckThread->run("BootAnimation::TimeCheckThread", PRIORITY_NORMAL);
     }
 
-    if (mAnimation != nullptr && mAnimation->dynamicColoringEnabled) {
+    if (mAnimation->dynamicColoringEnabled) {
         initDynamicColors();
     }