linux-variscite: Update to latest revision

Include the following commits:

2e10ac0319a imx8m-var-dart: spi: Use GPIO based CS0 chip select.
399d0debc00 brcmfmac: stop watchdog before detach and free everything
ff273daca01 brcmfmac: Add support for bcm43364 wireless chipset

recipes-kernel/linux/linux-variscite_4.9.51.bb

@@ -26,7 +26,7 @@ DEFCONFIG_mx8 = "imx8m_var_dart_defconfig"
 
 KERNEL_SRC ?= "git://github.com/varigit/linux-imx;protocol=git"
 SRC_URI = "${KERNEL_SRC};branch=${SRCBRANCH}"
-SRCREV = "e4e642a6bbaa73acc0dfcf3225eaf32da50305c8"
+SRCREV = "2e10ac0319a46619d94f275fe618103eecbe2b2c"
 
 S = "${WORKDIR}/git"