docs: clarify anti-rollback secure version bits for c2/c5

docs/en/api-reference/system/ota.rst

@@ -149,6 +149,8 @@ A brief description of where the states are set:
 Anti-rollback
 -------------
 
+{IDF_TARGET_SECURE_VERSION_EFUSE_BITS:default = "16", esp32 = "32", esp32c2 = "4", esp32c5 = "9"}
+
 Anti-rollback prevents rollback to application with security version lower than one programmed in eFuse of chip.
 
 This function works if set :ref:`CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK` option. In the bootloader, when selecting a bootable application, an additional security version check is added which is on the chip and in the application image. The version in the bootable firmware must be greater than or equal to the version in the chip.
@@ -204,8 +206,7 @@ Restrictions:
 
 .. list::
 
-    :esp32: - The number of bits in the ``secure_version`` field is limited to 32 bits. This means that only 32 times you can do an anti-rollback. You can reduce the length of this efuse field using :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` option.
-    :not esp32: - The number of bits in the ``secure_version`` field is limited to 16 bits. This means that only 16 times you can do an anti-rollback. You can reduce the length of this efuse field using :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` option.
+    - The number of bits in the ``secure_version`` field is limited to {IDF_TARGET_SECURE_VERSION_EFUSE_BITS} bits. This means that only {IDF_TARGET_SECURE_VERSION_EFUSE_BITS} times you can do an anti-rollback. You can reduce the length of this efuse field using :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` option.
     :esp32: - Anti-rollback works only if the encoding scheme for efuse is set to ``NONE``.
     - Factory and Test partitions are not supported in anti rollback scheme and hence partition table should not have partition with SubType set to ``factory`` or ``test``.
 

docs/zh_CN/api-reference/system/ota.rst

@@ -149,6 +149,8 @@ Kconfig 中的 :ref:`CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE` 可以帮助用户
 防回滚
 ------
 
+{IDF_TARGET_SECURE_VERSION_EFUSE_BITS:default = "16", esp32 = "32", esp32c2 = "4", esp32c5 = "9"}
+
 防回滚机制可以防止回滚到安全版本号低于芯片 eFuse 中烧录程序的应用程序版本。
 
 设置 :ref:`CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK`，启动防回滚机制。在引导加载程序中选取可启动的应用程序，会额外检查芯片和应用程序镜像的安全版本号。可启动固件中的应用安全版本号必须等于或高于芯片中的应用安全版本号。
@@ -204,8 +206,7 @@ Kconfig 中的 :ref:`CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE` 可以帮助用户
 
 .. list::
 
-    :esp32: - ``secure_version`` 字段最多有 32 位。也就是说，防回滚最多可以做 32 次。用户可以使用 :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` 减少该 eFuse 字段的长度。
-    :not esp32: - ``secure_version`` 字段最多有 16 位。也就是说，防回滚最多可以做 16 次。用户可以使用 :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` 减少该 eFuse 字段的长度。
+    - ``secure_version`` 字段最多有 {IDF_TARGET_SECURE_VERSION_EFUSE_BITS} 位。也就是说，防回滚最多可以做 {IDF_TARGET_SECURE_VERSION_EFUSE_BITS} 次。用户可以使用 :ref:`CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD` 减少该 eFuse 字段的长度。
     :esp32: - 防回滚仅在 eFuse 编码机制设置为 ``NONE`` 时生效。
     - 防回滚不支持工厂和测试分区，因此分区表中不应有设置为 ``工厂`` 或 ``测试`` 的分区。