Move PHYLIB to Kconfig

Signed-off-by: Alexandru Gagniuc <alex.g@adaptrum.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/configs/bk4r1_defconfig b/configs/bk4r1_defconfig
index 539ed6f..e991a04 100644
--- a/configs/bk4r1_defconfig
+++ b/configs/bk4r1_defconfig
@@ -33,6 +33,7 @@
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_SPI_FLASH_MTD=y
+CONFIG_PHYLIB=y
 CONFIG_DM_SERIAL=y
 CONFIG_FSL_LPUART=y
 CONFIG_DM_SPI=y