Merge pull request #6911 from aabadie/stm32l4_cpuid

cpu/stm32l4/ldscripts: fix stm32l476rg cpuid base address

cpu/stm32l4/ldscripts/stm32l476rg.ld

@@ -22,7 +22,7 @@ MEMORY
 {
     rom (rx)    : ORIGIN = 0x08000000, LENGTH = 1024K
     ram (rwx)   : ORIGIN = 0x20000000, LENGTH = 128K
-    cpuid (r)   : ORIGIN = 0x1ff80050, LENGTH = 12
+    cpuid (r)   : ORIGIN = 0x1fff7590, LENGTH = 12
 }
 
 _cpuid_address = ORIGIN(cpuid);