power: stpmu1: rename files to stpmic1

Prepare file modification for kernel alignment and
rename driver to stpmic1.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
diff --git a/board/st/stm32mp1/board.c b/board/st/stm32mp1/board.c
index 5f31ea9..1bb9779 100644
--- a/board/st/stm32mp1/board.c
+++ b/board/st/stm32mp1/board.c
@@ -8,7 +8,7 @@
 #include <asm/io.h>
 #include <asm/arch/ddr.h>
 #include <power/pmic.h>
-#include <power/stpmu1.h>
+#include <power/stpmic1.h>
 
 #ifdef CONFIG_DEBUG_UART_BOARD_INIT
 void board_debug_uart_init(void)