* Start getting rid of strncpy

* steam.c - cleanups:
  * Use string_to_lower from libretro-common/stdstring.c instead of
    its own version
  * Some stylistic changes
  * Rewrite strncpy calls into strlcpy/strlcat/manual assignment
  * Make it C89 compliant
  * Some unused variables

frontend/drivers/platform_ps2.c

@@ -271,7 +271,7 @@ static int mount_hdd_partition(void)
    if (bootDeviceID == BOOT_DEVICE_HDD || bootDeviceID == BOOT_DEVICE_HDD0)
    {
       /* If we're booting from HDD, we must update the cwd variable and add : to the mount point */
-      strncpy(cwd, new_cwd, sizeof(cwd));
+      strlcpy(cwd, new_cwd, sizeof(cwd));
       strlcat(mountPoint, ":", sizeof(mountPoint));
    }
    else

gfx/drivers/gx2_gfx.c

@@ -1490,14 +1490,13 @@ static bool wiiu_gfx_set_shader(void *data,
    for (i = 0; i < wiiu->shader_preset->passes; i++)
    {
       unsigned j;
+      char *ptr;
       char gfdpath[PATH_MAX_LENGTH];
       struct video_shader_pass *pass = &wiiu->shader_preset->pass[i];
 
-      strncpy(gfdpath, pass->source.path, PATH_MAX_LENGTH);
+      strlcpy(gfdpath, pass->source.path, sizeof(gfdpath));
 
-      char *ptr = strrchr(gfdpath, '.');
-
-      if (!ptr)
+      if (!(ptr = strrchr(gfdpath, '.')))
          ptr = gfdpath + strlen(gfdpath);
 
       *ptr++ = '.';