btmgmt: Add support to accept multiple PHY options

btmgmt: Add support to accept multiple PHY options

Before fix-
  [hci1]# phy 1MTX 1MRX 2MTX
  Too many arguments: 3 > 1

After Fix-
  [hci1]# phy 1MRX 1MTX 2MTX
  PHY Configuration successfully set

 btmon output -
 @ MGMT Command: Set PHY Configuration (0x0045) plen 4
         Selected PHYs: 0x0e00
           LE 1M TX
           LE 1M RX
           LE 2M TX
 < HCI Command: LE Set Default PHY (0x08|0x0031) plen 3
         All PHYs preference: 0x00
         TX PHYs preference: 0x03
           LE 1M
           LE 2M
         RX PHYs preference: 0x01
           LE 1M
 > HCI Event: Command Complete (0x0e) plen 4
        LE Set Default PHY (0x08|0x0031) ncmd 1
         Status: Success (0x00)
 @ MGMT Event: Command Complete (0x0001) plen 3
        Set PHY Configuration (0x0045) plen 0
         Status: Success (0x00)
 @ MGMT Event: PHY Configuration Changed (0x0026) plen 4
         Selected PHYs: 0x0e00
           LE 1M TX
           LE 1M RX
           LE 2M TX

Change-Id: I22e38e6d381b4c5aefc5a38314fd188874c7d83e
Signed-off-by: himanshu <h.himanshu@samsung.com>