Prepare metadata of BL2 and specify metadata address for BL1

[tdrozdovsky]

To operate a Secure Boot, metadata of BL2 must be available to BL1 at system startup.
fwinfogen.c must generate a structure describing BL2, in a way similar to shown below.

const uint32_t g_InitialFWinfo[] =
{
  /* public key - 64-bytes (256-bits + 256-bits) */
  0x5b8695d1, 0xe183b68e, 0xa924c9b5, 0x7d006c3e,
  0xc59cef2e, 0x7553a8bf, 0xd6edba7e, 0xd61fc965,
  0xd26e436c, 0x6a302846, 0xabc1cb13, 0xb06b850e,
  0x691f3afe, 0x85ed36bc, 0x314d5e2f, 0xfb5b2b24,

  /* metadata data - includes Mode selection, F/W region and Extend info */
  0x00000001, 0x00000008, 0x10040000, 0x00010a48, // 0x00020000: NuBL32 F/W base
  0x0000000c, 0x20191219, 0x00001111, 0x22223333, // 0x20180824/0x00001111/0x22223333: Extend info

  /* FW hash - 32-bytes (256-bits) */
  0x8bba8d7b, 0x52788b97, 0x60a12a8a, 0xa827f204,
  0xef5db443, 0x6bed61ce, 0xadcefa21, 0x8ef9c55b,

  /* FwInfo signature - 64-bytes (256-bits R + 256-bits S) */
  0x9a11cc48, 0x1bcd859a, 0x39c8e943, 0x148cd93d,
  0x96290f3c, 0xeb84455c, 0x873e4706, 0x5f8f09c7,
  0x54619ff9, 0x30f52a30, 0x221e366f, 0x35c15536,
  0x8254b390, 0x6c598a09, 0x3c0e9ec7, 0x7da9e940,
};