ARM: at91: Kconfig: Update company to Microchip

Update AT91 Kconfig text and help to move from Atmel to Microchip.
The AT91 wording is kept in the title for historical reasons.
Signed-off-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>

arch/arm/mach-at91/Kconfig

 menuconfig ARCH_AT91
-	bool "Atmel SoCs"
+	bool "AT91/Microchip SoCs"
 	depends on ARCH_MULTI_V4T || ARCH_MULTI_V5 || ARCH_MULTI_V7 || ARM_SINGLE_ARMV7M
 	select ARM_CPU_SUSPEND if PM && ARCH_MULTI_V7
 	select COMMON_CLK_AT91
@@ -13,7 +13,7 @@ config SOC_SAMV7
 	select COMMON_CLK_AT91
 	select PINCTRL_AT91
 	help
-	  Select this if you are using an SoC from Atmel's SAME7, SAMS7 or SAMV7
+	  Select this if you are using an SoC from Microchip's SAME7, SAMS7 or SAMV7
 	  families.
 
 config SOC_SAMA5D2
@@ -29,7 +29,7 @@ config SOC_SAMA5D2
 	select HAVE_AT91_AUDIO_PLL
 	select PINCTRL_AT91PIO4
 	help
-	  Select this if ou are using one of Atmel's SAMA5D2 family SoC.
+	  Select this if ou are using one of Microchip's SAMA5D2 family SoC.
 
 config SOC_SAMA5D3
 	bool "SAMA5D3 family"
@@ -41,7 +41,7 @@ config SOC_SAMA5D3
 	select HAVE_AT91_USB_CLK
 	select PINCTRL_AT91
 	help
-	  Select this if you are using one of Atmel's SAMA5D3 family SoC.
+	  Select this if you are using one of Microchip's SAMA5D3 family SoC.
 	  This support covers SAMA5D31, SAMA5D33, SAMA5D34, SAMA5D35, SAMA5D36.
 
 config SOC_SAMA5D4
@@ -56,7 +56,7 @@ config SOC_SAMA5D4
 	select HAVE_AT91_H32MX
 	select PINCTRL_AT91
 	help
-	  Select this if you are using one of Atmel's SAMA5D4 family SoC.
+	  Select this if you are using one of Microchip's SAMA5D4 family SoC.
 
 config SOC_AT91RM9200
 	bool "AT91RM9200"
@@ -70,7 +70,7 @@ config SOC_AT91RM9200
 	select SOC_SAM_V4_V5
 	select SRAM if PM
 	help
-	  Select this if you are using Atmel's AT91RM9200 SoC.
+	  Select this if you are using Microchip's AT91RM9200 SoC.
 
 config SOC_AT91SAM9
 	bool "AT91SAM9"
@@ -88,7 +88,7 @@ config SOC_AT91SAM9
 	select SOC_SAM_V4_V5
 	select SRAM if PM
 	help
-	  Select this if you are using one of those Atmel SoC:
+	  Select this if you are using one of those Microchip SoC:
 	    AT91SAM9260
 	    AT91SAM9261
 	    AT91SAM9263