scripts: west: runners: nrfjprog: add erasepage op

Add a new operation that allows erasing pages.

Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
diff --git a/scripts/west_commands/runners/nrfjprog.py b/scripts/west_commands/runners/nrfjprog.py
index 15f147a..c1eebd3 100644
--- a/scripts/west_commands/runners/nrfjprog.py
+++ b/scripts/west_commands/runners/nrfjprog.py
@@ -87,6 +87,9 @@
                 cmd.append('--reset')
             if _op['option'] == 'RESET_PIN':
                 cmd.append('--pinreset')
+        elif op_type == 'erasepage':
+            cmd.append('--erasepage')
+            cmd.append(f"0x{_op['page']:08x}")
         else:
             raise RuntimeError(f'Invalid operation: {op_type}')