power: rename stpmu1 to official name stpmic1

Alignment with kernel driver name & binding
introduced by https://patchwork.kernel.org/cover/10761943/
to use the final marketing name = STPMIC1.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
index cfc91e8..8c1506c 100644
--- a/drivers/power/regulator/Makefile
+++ b/drivers/power/regulator/Makefile
@@ -24,4 +24,4 @@
 obj-$(CONFIG_$(SPL_)DM_REGULATOR_LP87565) += lp87565_regulator.o
 obj-$(CONFIG_$(SPL_)DM_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o
 obj-$(CONFIG_DM_REGULATOR_TPS65910) += tps65910_regulator.o
-obj-$(CONFIG_$(SPL_)DM_REGULATOR_STPMU1) += stpmic1.o
+obj-$(CONFIG_$(SPL_)DM_REGULATOR_STPMIC1) += stpmic1.o