all: Fix cases of Python variable assigned but never used.

This fixes ruff rule F841.

tools/mpremote/mpremote/console.py

@@ -172,5 +172,5 @@ else:
     try:
         set_conout_mode(mode, mask)
         VT_ENABLED = True
-    except WindowsError as e:
+    except WindowsError:
         VT_ENABLED = False

tools/mpremote/mpremote/pyboardextended.py

@@ -449,7 +449,7 @@ class PyboardCommand:
             try:
                 stat = os.lstat(self.data_ilistdir[0] + "/" + entry)
                 mode = stat.st_mode & 0xC000
-            except OSError as er:
+            except OSError:
                 mode = 0
             self.wr_str(entry)
             self.wr_u32(mode)

tools/mpy-tool.py

@@ -1120,7 +1120,6 @@ class RawCodeNative(RawCode):
 
         i_top = len(self.fun_data)
         i = 0
-        qi = 0
         while i < i_top:
             # copy machine code (max 16 bytes)
             i16 = min(i + 16, i_top)
@@ -1276,7 +1275,7 @@ def read_raw_code(reader, parent_name, qstr_table, obj_table, segments):
                 if native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA:
                     rodata_size = reader.read_uint()
                 if native_scope_flags & MP_SCOPE_FLAG_VIPERBSS:
-                    bss_size = reader.read_uint()
+                    reader.read_uint()  # bss_size
                 if native_scope_flags & MP_SCOPE_FLAG_VIPERRODATA:
                     reader.read_bytes(rodata_size)
                 if native_scope_flags & MP_SCOPE_FLAG_VIPERRELOC:
@@ -1285,10 +1284,10 @@ def read_raw_code(reader, parent_name, qstr_table, obj_table, segments):
                         if op == 0xFF:
                             break
                         if op & 1:
-                            addr = reader.read_uint()
+                            reader.read_uint()  # addr
                         op >>= 1
                         if op <= 5 and op & 1:
-                            n = reader.read_uint()
+                            reader.read_uint()  # n
             else:
                 assert kind == MP_CODE_NATIVE_ASM
                 native_n_pos_args = reader.read_uint()

tools/mpy_ld.py

@@ -471,7 +471,6 @@ def do_relocation_text(env, text_addr, r):
     # Extract relevant info about symbol that's being relocated
     s = r.sym
     s_bind = s.entry["st_info"]["bind"]
-    s_shndx = s.entry["st_shndx"]
     s_type = s.entry["st_info"]["type"]
     r_offset = r["r_offset"] + text_addr
     r_info_type = r["r_info_type"]