ARM: dts: STiH407-family: Provide interconnect clock for consumption in ST SDHCI

The STiH4{07,10} platform contains some interconnect clocks which are used
by various IPs.  If these clocks aren't handled correctly by ST's SDHCI
driver MMC will break and the following output can be observed:

[   13.916949] mmc0: Timeout waiting for hardware interrupt.
[   13.922349] sdhci: =========== REGISTER DUMP (mmc0)===========
[   13.928175] sdhci: Sys addr: 0x00000000 | Version:  0x00001002
[   13.933999] sdhci: Blk size: 0x00007040 | Blk cnt:  0x00000001
[   13.939825] sdhci: Argument: 0x00fffff0 | Trn mode: 0x00000013
[   13.945650] sdhci: Present:  0x1fff0206 | Host ctl: 0x00000011
[   13.951475] sdhci: Power:    0x0000000f | Blk gap:  0x00000080
[   13.957300] sdhci: Wake-up:  0x00000000 | Clock:    0x00003f07
[   13.963126] sdhci: Timeout:  0x00000004 | Int stat: 0x00000000
[   13.968952] sdhci: Int enab: 0x02ff008b | Sig enab: 0x02ff008b
[   13.974777] sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000
[   13.980602] sdhci: Caps:     0x21ed3281 | Caps_1:   0x00000000
[   13.986428] sdhci: Cmd:      0x0000063a | Max curr: 0x00000000
[   13.992252] sdhci: Host ctl2: 0x00000000
[   13.996166] sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x7c048200
[   14.001990] sdhci: ===========================================
[   14.009802] mmc0: Got data interrupt 0x02000000 even though no data operation was in progress.

Cc: stable@vger.kernel.org
Tested-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Patrice Chotard <patrice.chotard@st.com>