Remove unused dicts from backend_cairo. (matplotlib#24760)

They are unused since 15c39a3.

Author: anntzer

lib/matplotlib/backends/backend_cairo.py

@@ -72,35 +72,6 @@ def attr(field):
     return name, slant, weight
 
 
-# Mappings used for deprecated properties in RendererCairo, see below.
-_f_weights = {
-    100:          cairo.FONT_WEIGHT_NORMAL,
-    200:          cairo.FONT_WEIGHT_NORMAL,
-    300:          cairo.FONT_WEIGHT_NORMAL,
-    400:          cairo.FONT_WEIGHT_NORMAL,
-    500:          cairo.FONT_WEIGHT_NORMAL,
-    600:          cairo.FONT_WEIGHT_BOLD,
-    700:          cairo.FONT_WEIGHT_BOLD,
-    800:          cairo.FONT_WEIGHT_BOLD,
-    900:          cairo.FONT_WEIGHT_BOLD,
-    'ultralight': cairo.FONT_WEIGHT_NORMAL,
-    'light':      cairo.FONT_WEIGHT_NORMAL,
-    'normal':     cairo.FONT_WEIGHT_NORMAL,
-    'medium':     cairo.FONT_WEIGHT_NORMAL,
-    'regular':    cairo.FONT_WEIGHT_NORMAL,
-    'semibold':   cairo.FONT_WEIGHT_BOLD,
-    'bold':       cairo.FONT_WEIGHT_BOLD,
-    'heavy':      cairo.FONT_WEIGHT_BOLD,
-    'ultrabold':  cairo.FONT_WEIGHT_BOLD,
-    'black':      cairo.FONT_WEIGHT_BOLD,
-}
-_f_angles = {
-    'italic':  cairo.FONT_SLANT_ITALIC,
-    'normal':  cairo.FONT_SLANT_NORMAL,
-    'oblique': cairo.FONT_SLANT_OBLIQUE,
-}
-
-
 class RendererCairo(RendererBase):
     def __init__(self, dpi):
         self.dpi = dpi