Initialize prlights[lighti].flags.invalidate with 0 when calling

polymer_addlight().  I have no idea whether it's the 'right' thing,
but it fixes this:

Conditional jump or move depends on uninitialised value(s)
  at polymer_updatelights (polymer.c:5090)
  by polymer_drawrooms (polymer.c:938)
              . . .
Uninitialised value was created by a stack allocation
  at loadmaphack (engine.c:9482)

Fix another uninitialized access when rendering jpegs.

git-svn-id: https://svn.eduke32.com/eduke32@2069 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/build/src/polymer.c

@@ -1474,6 +1474,8 @@ int16_t             polymer_addlight(_prlight* light)
     prlights[lighti].flags.isinview = 0;
     prlights[lighti].flags.active = 1;
 
+    prlights[lighti].flags.invalidate = 0;
+
     prlights[lighti].planecount = 0;
     prlights[lighti].planelist = NULL;
 

polymer/eduke32/build/src/polymost.c

@@ -1708,7 +1708,12 @@ static int32_t gloadtile_hi(int32_t dapic,int32_t dapalnum, int32_t facen, hicre
         if ((filh = kopen4load(fn, 0)) < 0) return -1;
 
         picfil = (char *)Bmalloc(picfillen+1); if (!picfil) { kclose(filh); return 1; }
-        kread(filh, picfil, picfillen);
+        if (kread(filh, picfil, picfillen) != picfillen)
+            initprintf("warning: didn't fully read %s\n", fn);
+        // prevent
+        // Conditional jump or move depends on uninitialised value(s)
+        //  at kpegrend (kplib.c:1655)
+        picfil[picfillen] = 0;
         kclose(filh);
 
         // tsizx/y = replacement texture's natural size