android/hal-health: Add HDP .register_application method

android/hal-health: Add HDP .register_application method

Implementation of register_application is different compared
to other apis. Due to limited IPC_MTU and variable length of
fields from 'bthl_reg_param_t *', it is difficult to put them
in single command and send though IPC. So we split this command
multiple calls. First command will be called with opcode of
HAL_OP_HEALTH_REG_APP with 'struct hal_cmd_health_reg_app' data.
Later command will be called with opcode of
HAL_OP_HEALTH_MDEP with 'struct hal_cmd_health_mdep' data for
number_of_mdeps times. App id will be sent in response to
HAL_OP_HEALTH_REG_APP command.

This avoids increasing value of IPC_MTU and mainly because of
optional parameters in 'bthl_reg_param_t'. Incase of unfilled
optional parameters, fixed size arrays in hal commands will be
empty.