glcanon: fix foam INI value lookup

Previously searching for "[DISPLAY]" instead of "DISPLAY" would return "None" and re-set the default value instead of the INI file's value.

Author: snowgoer540

lib/python/rs274/glcanon.py

@@ -553,8 +553,8 @@ def __init__(self, s=None, lp=None, g=None):
                         self.dro_mm = temp
                         self.dro_in = temp
 
-                self.foam_w_height = float(self.inifile.find("[DISPLAY]", "FOAM_W") or 1.5)
-                self.foam_z_height = float(self.inifile.find("[DISPLAY]", "FOAM_Z") or 0)
+                self.foam_w_height = float(self.inifile.find("DISPLAY", "FOAM_W") or 1.5)
+                self.foam_z_height = float(self.inifile.find("DISPLAY", "FOAM_Z") or 0)
 
                 size = (self.inifile.find("DISPLAY", "CONE_BASESIZE") or None)
                 if size is not None: