DataServices: Qualify math functions with std:: namespace specifier (…

…AMReX-Codes#3406)

## Summary
As in the title. This fixes AMReX-Codes#3405.

## Additional background
I did briefly look at using `powi`, but I don't think the exponents are
known at compile time.

I also added some auto-generated source files to .gitignore.

.gitignore

@@ -61,4 +61,10 @@ Tutorials/EB/Donut/Exec/ls_plt*
 
 # local config
 Tools/GNUMake/Make.local
-Tools/GNUMake/Make.local-pre
+Tools/GNUMake/Make.local-pre
+
+# profparser
+BLProfParser.lex.yy.cpp
+BLProfParser.tab.H
+BLProfParser.tab.cpp
+BLProfParserNC.y

Src/Extern/amrdata/AMReX_DataServices.cpp

@@ -2488,7 +2488,7 @@ void DataServices::RunTimelinePF(std::map<int, std::string> &mpiFuncNames,
           int ntnSize(nameTagNames.size());
           ntnNumbers.resize(ntnSize, 0.0);
           if(ntnSize > 0) {
-            ntnMultiplier = pow(10, static_cast<int>( 1 + log10(ntnSize)));
+            ntnMultiplier = std::pow(10, static_cast<int>( 1 + std::log10(ntnSize)));
           }
           for(int i(0); i < ntnSize; ++i) {
             if(ntnMultiplier > 0.0) {
@@ -2501,7 +2501,7 @@ void DataServices::RunTimelinePF(std::map<int, std::string> &mpiFuncNames,
           int bnSize(barrierNames.size());
           bnNumbers.resize(bnSize, 0.0);
           if(bnSize > 0) {
-            bnMultiplier = pow(10, static_cast<int>( 1 + log10(bnSize)));
+            bnMultiplier = std::pow(10, static_cast<int>( 1 + std::log10(bnSize)));
           }
           for(int i(0); i < bnSize; ++i) {
             if(bnMultiplier > 0.0) {