init: document interface_* commands and ctl.* actions

  -f: force installation of the module even if the version of the running kernel

  and the version of the kernel for which the module was compiled do not match.

`interface_start <name>` \

`interface_restart <name>` \

`interface_stop <name>`

> Find the service that provides the interface _name_ if it exists and run the `start`, `restart`,

or `stop` commands on it respectively.  _name_ may be either a fully qualified HIDL name, in which

case it is specified as `<interface>/<instance>`, or an AIDL name, in which case it is specified as

`aidl/<interface>` for example `android.hardware.secure_element@1.1::ISecureElement/eSE1` or

`aidl/aidl_lazy_test_1`.

> Note that these commands only act on interfaces specified by the `interface` service option, not

on interfaces registered at runtime.

> Example usage of these commands: \

`interface_start android.hardware.secure_element@1.1::ISecureElement/eSE1`

will start the HIDL Service that provides the `android.hardware.secure_element@1.1` and `eSI1`

instance. \

`interface_start aidl/aidl_lazy_test_1` will start the AIDL service that

provides the `aidl_lazy_test_1` interface.

`load_system_props`

> (This action is deprecated and no-op.)

  `/sys/fs/ext4/${dev.mnt.blk.<mount_point>}/` to tune the block device

  characteristics in a device agnostic manner.

Init responds to properties that begin with `ctl.`.  These properties take the format of

`ctl.<command>` and the _value_ of the system property is used as a parameter, for example:

`SetProperty("ctl.start", "logd")` will run the `start` command on `logd`.  Note that these

properties are only settable; they will have no value when read.

`ctl.start` \

`ctl.restart` \

`ctl.stop`

> These are equivalent to using the `start`, `restart`, and `stop` commands on the service specified

by the _value_ of the property.

`ctl.interface_start` \

`ctl.interface_restart` \

`ctl.interface_stop`

> These are equivalent to using the `interface_start`, `interface_restart`, and `interface_stop`

commands on the interface specified by the _value_ of the property.

`ctl.sigstop_on` and `ctl.sigstop_off` will turn on or off the _sigstop_ feature for the service

specified by the _value_ of the property.  See the _Debugging init_ section below for more details

about this feature.

Boot timing

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