Draft: arm64: dts: imx8mq-librem5: Keep SD card powered during system suspend

If the SD card fails to reinitialize before attempting to use it, it may fail on resume:

[  525.132554] sd 0:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x00 driverbyte=DRIVER_OK cmd_age=0s
[  525.132580] sd 0:0:0:0: [sda] tag#0 Sense Key : 0x6 [current]
[  525.132587] sd 0:0:0:0: [sda] tag#0 ASC=0x28 ASCQ=0x0
[  525.132596] sd 0:0:0:0: [sda] tag#0 CDB: opcode=0x2a 2a 00 00 00 59 48 00 00 f0 00
[  525.132603] I/O error, dev sda, sector 22856 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.145723] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.151582] I/O error, dev sda, sector 23096 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.161615] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.167428] I/O error, dev sda, sector 23336 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.176633] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.182468] I/O error, dev sda, sector 23576 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.191597] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.197429] I/O error, dev sda, sector 23816 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.206509] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.212342] I/O error, dev sda, sector 24056 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.221392] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.227186] I/O error, dev sda, sector 24296 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.236191] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.241999] I/O error, dev sda, sector 24536 op 0x1:(WRITE) flags 0x4000 phys_seg 30 prio class 2
[  525.251009] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.256819] I/O error, dev sda, sector 24776 op 0x1:(WRITE) flags 0x0 phys_seg 16 prio class 2
[  525.265547] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.271336] I/O error, dev sda, sector 24904 op 0x1:(WRITE) flags 0x4800 phys_seg 30 prio class 2
[  525.280321] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.286130] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.291986] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.297797] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.303661] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.309526] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.315353] sd 0:0:0:0: [sda] tag#0 device offline or changed
[  525.321203] sd 0:0:0:0: [sda] tag#0 device offline or changed